11.7D: Basal Ganglia
The basal ganglia is important for the control of movement and forming habits, and each of its components has a complex internal anatomical and neurochemical organization.
LEARNING OBJECTIVE
Describe the functions of the basal ganglia
Key Takeaways
Key Points
- The basal ganglia are a group of nuclei of varied origin in the brains of vertebrates that act as a cohesive functional unit.
- The basal ganglia are associated with a variety of functions including voluntary motor control, procedural learning relating to routine behaviors or “habits” such as bruxism, eye movements, cognitive, and emotional functions.
- The basal ganglia are composed of the striatum, the pallidum, the substantia nigra, and the subthalamic nucleus.
- The basal ganglia play a central role in a number of neurological conditions including Parkinson’s disease and Huntington’s disease.
Key Terms
- Huntington’s disease : A neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and psychiatric problems.
- Parkinson’s disease : A chronic neurological disorder resulting in lack of control over movement; poor balance and coordination; and similar symptoms.
- executive functions : Also known as cognitive control and supervisory attentional system. Refers to a set of cognitive processes, including attentional control, inhibitory control, working memory, and cognitive flexibility, reasoning, problem solving, and planning.
- bruxism : Excessive grinding and clenching of the teeth.
The basal ganglia (or basal nuclei) are a group of nuclei of varied origin in the brains of vertebrates that act as a cohesive functional unit. They are situated at the base of the forebrain and are strongly connected with the cerebral cortex, thalamus, and other brain areas. The components of the basal ganglia include the striatum, pallidum, substantia nigra, and subthalamic nucleus. Each of these components has a complex internal anatomical and neurochemical organization.
Structure
The Basal Ganglia: The basal nuclei are often referred to as the basal ganglia. The main components of the basal nuclei are labeled in purple.
The main components of the basal ganglia are:
- Striatum, or neostriatum: This component consists of 3 divisions: the caudate, putamen, and ventral striatum (includes the nucleus accumbens). The striatum receives input from many brain areas, but sends output only to other components of the basal ganglia.
- Globus pallidus, or pallidum: This component is composed of the globus pallidus externa (GPe) and globus pallidus interna (GPi). The pallidum receives its most important input from the striatum (either directly or indirectly), and sends inhibitory output to a number of motor-related areas, including the part of the thalamus that projects to the motor-related areas of the cortex.
- Substantia nigra: This component consists of the substantia nigra pars compacta (SNc) and substantia nigra pars reticulata (SNr). The SNr functions similarly to the pallidum, and the SNc cells contain neuromelanin and produce dopamine (a neurotransmitter) for input to the striatum.
- Subthalamic nucleus (STN): The STN receives input mainly from the striatum and cortex, and projects to a portion of the pallidum (interna portion or GPi). It is the only portion of the ganglia that produces an excitatory neurotransmitter, glutamate. The role of the subthalamic nucleus is to stimulate the SNr-GPi complex, and it receives inhibitory input from the GPe and sends excitatory signal to the GPi.
Function
The basal ganglia are associated with a variety of functions, including voluntary motor control, procedural learning relating to routine behaviors or habits such as bruxism, eye movements, and cognitive, emotional functions. Currently, popular theories implicate the basal ganglia primarily in action selection, that is, the decision of which several possible behaviors to execute at a given time. Experimental studies show that the basal ganglia exert an inhibitory influence on a number of motor systems and that a release of this inhibition permits a motor system to become active. The behavior switching that takes place within the basal ganglia is influenced by signals from many parts of the brain, including the prefrontal cortex, which plays a key role in executive functions.
The basal ganglia play a central role in a number of neurological conditions, including several movement disorders. The most notable are Parkinson’s disease, which involves degeneration of the melanin-pigmented dopamine-producing cells in the substantia nigra pars compacta (SNc), and Huntington’s disease, which primarily involves damage to the striatum. Basal ganglia dysfunction is also implicated in some other disorders of behavior control such as Tourette’s syndrome, ballismus (particularly hemibalismus), obsessive-compulsive disorder, and Wilson’s disease (hepatolenticular degeneration). With the exception of Wilson’s disease and hemiballismus, the neuropathological mechanisms underlying diseases of ganglia such as Parkinsons’ and Huntington’s are not very well understood or are at best still developing theories.
The basal ganglia have a limbic sector whose components are the nucleus accumbens, ventral pallidum, and ventral tegmental area (VTA). This limbic sector is thought to play a central role in reward learning, particularly a pathway from the VTA to the nucleus accumbens that uses the neurotransmitter dopamine. A number of highly addictive drugs, including cocaine, amphetamine, and nicotine, are thought to work by increasing the efficacy of this dopamine signal.


2.2: Main Health Needs (Reasons for Seeking Care)
The client’s main health needs are referred to in a variety of ways depending on the environment or institution that you work in. At first point of contact, “main health needs” are often referred to as “ reasons for seeking care ” or “chief concerns or issues.” In an institution where the client is already admitted, “ main health needs ” is more commonly used.
Whichever term is used, it recognizes that clients are complex beings, with potentially multiple co-existing health needs, and often there is a pressing issue that requires most immediate care. This is not to suggest that other issues be ignored, but rather it allows providers, clients, and care partners to stay focused.
Most often, providers will document in the client’s own words what the main health needs are. Table 2.2 offers example questions to ask to determine a client’s main health needs in different scenarios, along with sample responses.
It is important to avoid asking questions that begin with “why,” which may suggest to the client that they did something wrong or that they are to blame for what is happening to them.
| Client | Assessment | Sample Responses |
|---|---|---|
|
Presenting to a clinic or a hospital emergency or urgent care (first point of contact). |
Tell me about what brought you here today. Probes
|
|
| Already admitted, and you are starting your shift. |
Tell me about your main health concerns today. Probes
|
|
Take Action
As a health professional, you need to identify whether a client’s symptomology is considered: normal ; abnormal and requiring intervention; or a critical finding that requires prompt intervention. Your subjective data assessment may be cut short if critical findings arise that require immediate intervention. In such a case, you focus on the critical finding and resume the complete subjective health assessment later, when appropriate. Some findings, even though normal, will require health promotion interventions.
Examples of subjective data that are identified as critical findings and require prompt intervention include but are not limited to:
- Chest pain.
- Severe difficulty breathing.
- Sudden change in vision or ability to speak.
- Sudden weakness or paralysis in a limb.
- Uncontrollable bleeding.
- Post-operative pain or vomiting not relieved by medication.
- Suicidal or homicidal ideation with a plan.
“Door-handle conversations” describe the situation of a client sharing something with a health professional just as they are about to leave the room (their hand is on the door handle as illustrated in Figure 2.1 ). Often it is at the last minute when clients gather the courage to speak about a health issue that they are embarrassed or feel shameful about. It may be about something that is stigmatized, or they feel they may be judged on. In these cases, it is important to make time for the client and listen in a non-judgmental manner.
Test Yourself
Query \(\PageIndex{1}\)


1.2: Net Income—A Critical Amount
The difference between the total revenue and total expense amounts for a particular period (such as a month or year), assuming revenue is higher, is profit. We will now refer to profit as net income . The following is a key calculation in determining a business’s operating results in dollars:
Revenue - Expenses = Net Income
Net income is determined by subtracting all expenses for a month (or year) from all revenue for that same month (or year). A net loss results if total expenses for a month (or year) exceed total revenue for the same period of time.
Net income is a result that business people are extremely interested in knowing since it represents the results of a firm’s operations in a given period of time.


13.4.6: Protecting Your Identity
-
- Last updated
- Save as PDF
- Anonymous
- LibreTexts
What You’ll Learn
- The difference between being anonymous and pseudonymous
- Three distinct ways to use Tor
- Some things you should never try to do using Tor
In the chapter “Anonymous Routing,” we compared and contrasted virtual private networks (VPNs) and Tor as two methods for disguising one’s metadata online. This can help one achieve anonymity or pseudonymity, but this is difficult to do over the long term. In this chapter, we will focus on skills for using Tor over VPN, but these lessons apply to using a VPN. One needs to additionally remember, though, that when using a VPN, the VPN provider knows who you are and the metadata of your internet communications (and the content, if it isn’t encrypted). While we will focus on using Tor via the Tor Browser, know that there are other applications (such as secure-messaging applications or whole operating systems) that route internet requests through the Tor network.
Anonymity versus Pseudonymity
Before we describe different ways to use Tor, let us consider the difference between anonymity and pseudonymity. These terms are used in different ways in different contexts, and we restrict our use here to online communications and behavior.
Anonymity refers to being without a name or, more generally, without any identifier that could link to you. If you visit a website anonymously today and the same website anonymously tomorrow, the website should not even be able to tell that it was the same person both times. All the website should know is that “someone visited me anonymously yesterday” and “someone visited me anonymously today.”
Pseudonymity refers to using a false name, with few or no people knowing your true identity. For example, Samuel Clemens published under the pseudonym Mark Twain, but of course his publisher and others knew who the true author was. Edward Snowden used the pseudonym Cincinnatus in contacting journalist Glenn Greenwald. Greenwald did not know who was contacting him as Cincinnatus, and because Snowden was using Tor to contact Greenwald, neither did anyone else. However, Snowden’s repeated use of the alias Cincinnatus allowed Greenwald to connect different communications he (and fellow journalist Laura Poitras) received from Snowden. We will refer to pseudonymity as allowing one to link different and otherwise anonymous sessions of communications under one persona.
Ways to Use Tor
Tor can be used to hide information about your identity (such as your physical location) and achieve anonymity and pseudonymity. For the novice user, Tor is accessed using the Tor Browser or Tor-compatible apps. For a more advanced user, non-web-browser communications can be routed through Tor by using an operating system (such as Tails or Whonix) that routes all your web traffic through Tor.
Hiding Your Physical Location
Using the Tor Browser as you do any other browser, including accessing emails or social media usernames that are linked to you, will conceal your physical location from those accounts. Each time you open a new Tor Browser tab or window and after a certain delay, Tor will route your web requests via a new location. However, many email and social media platforms will flag your account activity as suspicious if it is being accessed from different locations, as it will appear to be when accessing through Tor. So while it is possible to use Tor all the time and for everything, it may not be practical. If you are able to navigate these difficulties, you will still need to be smart to consistently hide your physical location by avoiding the following behaviors:
- Entering identifying information into a website (such as your address)
- Downloading a document that might access some part of the document via the web (like a photo) and opening it outside the Tor Browser (Word documents and pdfs can do this); if you need to access such a document, disconnect from the internet before opening
Achieving Anonymity
Using Tor can help you achieve anonymity. However, you will need to restrict your behavior to ensure you don’t leak information that could break your anonymity. To that end, in order to maintain anonymity, you need to avoid the following behaviors during your anonymous session (in addition to those for hiding your physical location):
- Logging into accounts (e.g., social media, email, banking)
- Visiting your own website repeatedly
Achieving and Maintaining Pseudonymity
If you create a pseudonym that is unrelated to your true identity in order to, for example, post press releases or participate in forums, Tor can help ensure that your pseudonym stays unrelated to your true identity. However, to keep your real and pseudonymous identity separate, you need to avoid the following behaviors:
- Accessing different pseudonymous (or your pseudonymous and real) identities in the same session, as this can link these identities
- Accessing a pseudonymous account even once outside of Tor
- Using two-factor authentication with a phone (as your phone, even if it is a “burner,” can reveal your physical location)
- Posting media with revealing metadata (such as location)
Note that the longer you attempt to maintain a pseudonymous identity, the more opportunity you give yourself to make a mistake. In addition to the mistakes above, your writing style can be used to identify you using stylometry. The more examples of your writing style that are available (under both your real and pseudonymous identity), the easier it would be to identify you.
Tor Warnings
There are some additional things to be aware of when accessing the internet via Tor.
As with any protective technology, nothing is perfect. If an adversary (Edgar) is able to watch Assata’s connection to the Tor network as well her connection leaving the Tor network (to Bobby’s website), Edgar will be able to determine that Assata is visiting Bobby’s website. This is called an end-to-end timing attack or correlation attack.
If you attempt to use applications not designed for Tor over the Tor network, they may leak identifying information, such as screen resolution or a unique set of settings you may have.
Finally, when using Tor, keep in mind it only provides anonymity—for privacy, you need to be accessing web pages using end-to-end encryption via https (though unfortunately not all websites support this).
In Context: Getting the Real Tor Browser
The tools you use to protect yourself online are only useful if they are the real thing. In 2019, it was discovered that a false version of the Tor Browser was being promoted by people interested in (and successfully) stealing Bitcoin. They made the malicious “Tor Browser” available through incorrect domains like tor-browser[.]org and torproect[.]org (instead of the authentic domain, torproject.org). To protect yourself from such mistakes as downloading from the wrong site or to protect yourself from a man-in-the-middle attack that supplies you with a malicious app, apps such as the Tor Browser make it possible for you to check the signature of a download, as we discussed in the chapter “Public-Key Cryptography.”
External Resources
- Hancock, Alexis. “ Phony HTTPS Everywhere Extension Used in Fake Tor Browser .” Electronic Frontier Foundation, October 31, 2019.
- Tails . Accessed February 9, 2021.
- Tor Project. “ Tor Project: Overview .” Accessed February 9, 2021.
- Whonix. “ Tips on Remaining Anonymous .” December 26, 2020.
- Whonix. “ Whonix: Software That Can Anonymize Everything You Do Online .” Accessed February 9, 2021.


11.2.5: How to Incorporate Data Files in Your Code Blocks- For R
There are a number of ways data files and can be incorporated into code blocks. However, ensure that you have already followed the steps in the introduction to the CKEditor Binder Plugin Tutorial here .
Method 1: Using read.csv
the url for the file can be saved to a variable or be added in all at once as shown below.
Keep in mind that larger data files will take longer to load.
Method 2: Using wget or curl through download.file
Another option to load in a data file is using wget or curl through the download.file function. An example code block is shown below, replace your url with the one in the example. For more information about the download.file function visit this link .


1.9: Temperature and Heat (Exercises)
Conceptual Questions
1.1: Temperature and Thermal Equilibrium
1. What does it mean to say that two systems are in thermal equilibrium?
2. Give an example in which A has some kind of non-thermal equilibrium relationship with B, and B has the same relationship with C, but A does not have that relationship with C.
1.2: Thermometers and Temperature Scales
3. If a thermometer is allowed to come to equilibrium with the air, and a glass of water is not in equilibrium with the air, what will happen to the thermometer reading when it is placed in the water?
4. Give an example of a physical property that varies with temperature and describe how it is used to measure temperature.
1.3: Thermal Expansion
5. Pouring cold water into hot glass or ceramic cookware can easily break it. What causes the breaking? Explain why Pyrex®, a glass with a small coefficient of linear expansion, is less susceptible.
6 . One method of getting a tight fit, say of a metal peg in a hole in a metal block, is to manufacture the peg slightly larger than the hole. The peg is then inserted when at a different temperature than the block. Should the block be hotter or colder than the peg during insertion? Explain your answer.
7 . Does it really help to run hot water over a tight metal lid on a glass jar before trying to open it? Explain your answer.
8. When a cold alcohol thermometer is placed in a hot liquid, the column of alcohol goes down slightly before going up. Explain why.
9. Calculate the length of a 1-meter rod of a material with thermal expansion coefficient αα when the temperature is raised from 300 K to 600 K. Taking your answer as the new initial length, find the length after the rod is cooled back down to 300 K. Is your answer 1 meter? Should it be? How can you account for the result you got?
10. Noting the large stresses that can be caused by thermal expansion, an amateur weapon inventor decides to use it to make a new kind of gun. He plans to jam a bullet against an aluminum rod inside a closed invar tube. When he heats the tube, the rod will expand more than the tube and a very strong force will build up. Then, by a method yet to be determined, he will open the tube in a split second and let the force of the rod launch the bullet at very high speed. What is he overlooking?
1.4: Heat Transfer, Specific Heat, and Calorimetry
11. How is heat transfer related to temperature?
12. Describe a situation in which heat transfer occurs.
13. When heat transfers into a system, is the energy stored as heat? Explain briefly.
14. The brakes in a car increase in temperature by ΔT when bringing the car to rest from a speed \(v\). How much greater would ΔT be if the car initially had twice the speed? You may assume the car stops fast enough that no heat transfers out of the brakes.
1.5: Phase Changes
15. A pressure cooker contains water and steam in equilibrium at a pressure greater than atmospheric pressure. How does this greater pressure increase cooking speed?
16. As shown below, which is the phase diagram for carbon dioxide, what is the vapor pressure of solid carbon dioxide (dry ice) at −78.5°C?−78.5°C? (Note that the axes in the figure are nonlinear and the graph is not to scale.)
17. Can carbon dioxide be liquefied at room temperature ( 20°C )? If so, how? If not, why not? (See the phase diagram in the preceding problem.)
18. What is the distinction between gas and vapor?
19. Heat transfer can cause temperature and phase changes. What else can cause these changes?
20. How does the latent heat of fusion of water help slow the decrease of air temperatures, perhaps preventing temperatures from falling significantly below 0°C, in the vicinity of large bodies of water?
21. What is the temperature of ice right after it is formed by freezing water?
22. If you place 0°C ice into 0°C water in an insulated container, what will the net result be? Will there be less ice and more liquid water, or more ice and less liquid water, or will the amounts stay the same?
23. What effect does condensation on a glass of ice water have on the rate at which the ice melts? Will the condensation speed up the melting process or slow it down?
24. In Miami, Florida, which has a very humid climate and numerous bodies of water nearby, it is unusual for temperatures to rise above about 38°C ( 100°F ). In the desert climate of Phoenix, Arizona, however, temperatures rise above that almost every day in July and August. Explain how the evaporation of water helps limit high temperatures in humid climates.
25. In winter, it is often warmer in San Francisco than in Sacramento, 150 km inland. In summer, it is nearly always hotter in Sacramento. Explain how the bodies of water surrounding San Francisco moderate its extreme temperatures.
26. Freeze-dried foods have been dehydrated in a vacuum. During the process, the food freezes and must be heated to facilitate dehydration. Explain both how the vacuum speeds up dehydration and why the food freezes as a result.
27. In a physics classroom demonstration, an instructor inflates a balloon by mouth and then cools it in liquid nitrogen. When cold, the shrunken balloon has a small amount of light blue liquid in it, as well as some snow-like crystals. As it warms up, the liquid boils, and part of the crystals sublime, with some crystals lingering for a while and then producing a liquid. Identify the blue liquid and the two solids in the cold balloon. Justify your identifications using data from Table 1.4.
1.6: Mechanisms of Heat Transfer
28. What are the main methods of heat transfer from the hot core of Earth to its surface? From Earth’s surface to outer space?
29. When our bodies get too warm, they respond by sweating and increasing blood circulation to the surface to transfer thermal energy away from the core. What effect will those processes have on a person in a 40.0-°C hot tub?
30. Shown below is a cut-away drawing of a thermos bottle (also known as a Dewar flask), which is a device designed specifically to slow down all forms of heat transfer. Explain the functions of the various parts, such as the vacuum, the silvering of the walls, the thin-walled long glass neck, the rubber support, the air layer, and the
31. Some electric stoves have a flat ceramic surface with heating elements hidden beneath. A pot placed over a heating element will be heated, while the surface only a few centimeters away is safe to touch. Why is ceramic, with a conductivity less than that of a metal but greater than that of a good insulator, an ideal choice for the stove top?
32. Loose-fitting white clothing covering most of the body, shown below, is ideal for desert dwellers, both in the hot Sun and during cold evenings. Explain how such clothing is advantageous during both day and night.
33. One way to make a fireplace more energy-efficient is to have room air circulate around the outside of the fire box and back into the room. Detail the methods of heat transfer involved.
34. On cold, clear nights horses will sleep under the cover of large trees. How does this help them keep warm?
35 . When watching a circus during the day in a large, dark-colored tent, you sense significant heat transfer from the tent. Explain why this occurs.
36. Satellites designed to observe the radiation from cold (3 K) dark space have sensors that are shaded from the Sun, Earth, and the Moon and are cooled to very low temperatures. Why must the sensors be at low temperature?
37. Why are thermometers that are used in weather stations shielded from the sunshine? What does a thermometer measure if it is shielded from the sunshine? What does it measure if it is not?
38. Putting a lid on a boiling pot greatly reduces the heat transfer necessary to keep it boiling. Explain why.
39. Your house will be empty for a while in cold weather, and you want to save energy and money. Should you turn the thermostat down to the lowest level that will protect the house from damage such as freezing pipes, or leave it at the normal temperature? (If you don’t like coming back to a cold house, imagine that a timer controls the heating system so the house will be warm when you get back.) Explain your answer.
40. You pour coffee into an unlidded cup, intending to drink it 5 minutes later. You can add cream when you pour the cup or right before you drink it. (The cream is at the same temperature either way. Assume that the cream and coffee come into thermal equilibrium with each other very quickly.) Which way will give you hotter coffee? What feature of this question is different from the previous one?
41. Broiling is a method of cooking by radiation, which produces somewhat different results from cooking by conduction or convection. A gas flame or electric heating element produces a very high temperature close to the food and above it. Why is radiation the dominant heat-transfer method in this situation?
42. On a cold winter morning, why does the metal of a bike feel colder than the wood of a porch?
Problems
1.2: Thermometers and Temperature Scales
43. While traveling outside the United States, you feel sick. A companion gets you a thermometer, which says your temperature is 39. What scale is that on? What is your Fahrenheit temperature? Should you seek medical help?
44. What are the following temperatures on the Kelvin scale?
(a) 68.0°F , an indoor temperature sometimes recommended for energy conservation in winter
(b) 134°F , one of the highest atmospheric temperatures ever recorded on Earth (Death Valley, California, 1913)
(c) 9890°F , the temperature of the surface of the Sun
45. (a) Suppose a cold front blows into your locale and drops the temperature by 40.0 Fahrenheit degrees. How many degrees Celsius does the temperature decrease when it decreases by 40.0°F ? (b) Show that any change in temperature in Fahrenheit degrees is nine-fifths the change in Celsius degrees
46. An Associated Press article on climate change said, “Some of the ice shelf’s disappearance was probably during times when the planet was 36 degrees Fahrenheit (2 degrees Celsius) to 37 degrees Fahrenheit (3 degrees Celsius) warmer than it is today.” What mistake did the reporter make?
47. (a) At what temperature do the Fahrenheit and Celsius scales have the same numerical value? (b) At what temperature do the Fahrenheit and Kelvin scales have the same numerical value?
48. A person taking a reading of the temperature in a freezer in Celsius makes two mistakes: first omitting the negative sign and then thinking the temperature is Fahrenheit. That is, the person reads –x°C as x°F . Oddly enough, the result is the correct Fahrenheit temperature. What is the original Celsius reading? Round your answer to three significant figures.
1.4: Heat Transfer, Specific Heat, and Calorimetry
49. The height of the Washington Monument is measured to be 170.00 m on a day when the temperature is 35.0°C . What will its height be on a day when the temperature falls to −10.0°C ? Although the monument is made of limestone, assume that its coefficient of thermal expansion is the same as that of marble. Give your answer to five significant figures.
50. How much taller does the Eiffel Tower become at the end of a day when the temperature has increased by 15°C ? Its original height is 321 m and you can assume it is made of steel.
51. What is the change in length of a 3.00-cm-long column of mercury if its temperature changes from 37.0°C to 40.0°C , assuming the mercury is constrained to a cylinder but unconstrained in length? Your answer will show why thermometers contain bulbs at the bottom instead of simple columns of liquid.
52. How large an expansion gap should be left between steel railroad rails if they may reach a maximum temperature 35.0°C greater than when they were laid? Their original length is 10.0 m.
53.  The price is “only” $60,000 per square meter. The land title says the dimensions are 20m×30m . By how much would the total price change if you measured the parcel with a steel tape measure on a day when the temperature was 20°C above the temperature that the tape measure was designed for? The dimensions of the land do not change.
54. Global warming will produce rising sea levels partly due to melting ice caps and partly due to the expansion of water as average ocean temperatures rise. To get some idea of the size of this effect, calculate the change in length of a column of water 1.00 km high for a temperature increase of 1.00°C . Assume the column is not free to expand sideways. As a model of the ocean, that is a reasonable approximation, as only parts of the ocean very close to the surface can expand sideways onto land, and only to a limited degree. As another approximation, neglect the fact that ocean warming is not uniform with depth.
55. (a) Suppose a meter stick made of steel and one made of aluminum are the same length at 0°C . What is their difference in length at 22.0°C ?
(b) Repeat the calculation for two 30.0-m-long surveyor’s tapes.
56. (a) If a 500-mL glass beaker is filled to the brim with ethyl alcohol at a temperature of 5.00°C , how much will overflow when the alcohol’s temperature reaches the room temperature of 22.0°C ?
(b) How much less water would overflow under the same conditions?
57. Most cars have a coolant reservoir to catch radiator fluid that may overflow when the engine is hot. A radiator is made of copper and is filled to its 16.0-L capacity when at 10.0°C. What volume of radiator fluid will overflow when the radiator and fluid reach a temperature of 95.0°C , given that the fluid’s volume coefficient of expansion is β=400×10−6/°C ? (Your answer will be a conservative estimate, as most car radiators have operating temperatures greater than 95.0°C ).
58. A physicist makes a cup of instant coffee and notices that, as the coffee cools, its level drops 3.00 mm in the glass cup. Show that this decrease cannot be due to thermal contraction by calculating the decrease in level if the \(350cm^3\) of coffee is in a 7.00-cm-diameter cup and decreases in temperature from 95.0°C to 45.0°C . (Most of the drop in level is actually due to escaping bubbles of air.)
59. The density of water at 0°C is very nearly \(1000kg/m^3\) (it is actually \(999.84kg/m^3\)), whereas the density of ice at 0°C 0°C is \(917kg/m^3\). Calculate the pressure necessary to keep ice from expanding when it freezes, neglecting the effect such a large pressure would have on the freezing temperature. (This problem gives you only an indication of how large the forces associated with freezing water might be.)
60. Show that β=3α , by calculating the infinitesimal change in volume dV of a cube with sides of length L when the temperature changes by dT.
1.4: Thermal Expansion
61. On a hot day, the temperature of an 80,000-L swimming pool increases by 1.50°C . What is the net heat transfer during this heating? Ignore any complications, such as loss of water by evaporation.
62. To sterilize a 50.0-g glass baby bottle, we must raise its temperature from 22.0°C to 95.0°C . How much heat transfer is required?
63. The same heat transfer into identical masses of different substances produces different temperature changes. Calculate the final temperature when 1.00 kcal of heat transfers into 1.00 kg of the following, originally at 20.0°C :
(a) water;
(b) concrete;
(c) steel; and
(d) mercury.
64. Rubbing your hands together warms them by converting work into thermal energy. If a woman rubs her hands back and forth for a total of 20 rubs, at a distance of 7.50 cm per rub, and with an average frictional force of 40.0 N, what is the temperature increase? The mass of tissues warmed is only 0.100 kg, mostly in the palms and fingers.
65. A 0.250-kg block of a pure material is heated from 20.0°C to 65.0°C by the addition of 4.35 kJ of energy. Calculate its specific heat and identify the substance of which it is most likely composed.
66. Suppose identical amounts of heat transfer into different masses of copper and water, causing identical changes in temperature. What is the ratio of the mass of copper to water?
67. (a) The number of kilocalories in food is determined by calorimetry techniques in which the food is burned and the amount of heat transfer is measured. How many kilocalories per gram are there in a 5.00-g peanut if the energy from burning it is transferred to 0.500 kg of water held in a 0.100-kg aluminum cup, causing a 54.9-°C temperature increase? Assume the process takes place in an ideal calorimeter, in other words a perfectly insulated container.
(b) Compare your answer to the following labeling information found on a package of dry roasted peanuts: a serving of 33 g contains 200 calories. Comment on whether the values are consistent.
68. Following vigorous exercise, the body temperature of an 80.0 kg person is 40.0°C. At what rate in watts must the person transfer thermal energy to reduce the body temperature to 37.0°C in 30.0 min, assuming the body continues to produce energy at the rate of 150 W? (1watt=1joule/secondor1W=1J/s)
69. In a study of healthy young \(men^1\), doing 20 push-ups in 1 minute burned an amount of energy per kg that for a 70.0-kg man corresponds to 8.06 calories (kcal). How much would a 70.0-kg man’s temperature rise if he did not lose any heat during that time?
70. A 1.28-kg sample of water at 10.0°C is in a calorimeter. You drop a piece of steel with a mass of 0.385 kg at 215°C into it. After the sizzling subsides, what is the final equilibrium temperature? (Make the reasonable assumptions that any steam produced condenses into liquid water during the process of equilibration and that the evaporation and condensation don’t affect the outcome, as we’ll see in the next section.)
71. Repeat the preceding problem, assuming the water is in a glass beaker with a mass of 0.200 kg, which in turn is in a calorimeter. The beaker is initially at the same temperature as the water. Before doing the problem, should the answer be higher or lower than the preceding answer? Comparing the mass and specific heat of the beaker to those of the water, do you think the beaker will make much difference?
1.5: Phase Changes
72. How much heat transfer (in kilocalories) is required to thaw a 0.450-kg package of frozen vegetables originally at 0°C if their heat of fusion is the same as that of water?
73. A bag containing 0°C ice is much more effective in absorbing energy than one containing the same amount of 0°C water.
(a) How much heat transfer is necessary to raise the temperature of 0.800 kg of water from 0°C to 30.0°C ?
(b) How much heat transfer is required to first melt 0.800 kg of 0°C ice and then raise its temperature?
(c) Explain how your answer supports the contention that the ice is more effective.
74. (a) How much heat transfer is required to raise the temperature of a 0.750-kg aluminum pot containing 2.50 kg of water from 30.0°C to the boiling point and then boil away 0.750 kg of water?
(b) How long does this take if the rate of heat transfer is 500 W?
75. Condensation on a glass of ice water causes the ice to melt faster than it would otherwise. If 8.00 g of vapor condense on a glass containing both water and 200 g of ice, how many grams of the ice will melt as a result? Assume no other heat transfer occurs. Use (L_v\) for water at 37°C as a better approximation than \(L_v\) for water at 100°C .)
76. On a trip, you notice that a 3.50-kg bag of ice lasts an average of one day in your cooler. What is the average power in watts entering the ice if it starts at 0°C and completely melts to 0°C water in exactly one day?
77. On a certain dry sunny day, a swimming pool’s temperature would rise by 1.50°C if not for evaporation. What fraction of the water must evaporate to carry away precisely enough energy to keep the temperature constant?
78. (a) How much heat transfer is necessary to raise the temperature of a 0.200-kg piece of ice from −20.0°C to 130.0°C , including the energy needed for phase changes?
(b) How much time is required for each stage, assuming a constant 20.0 kJ/s rate of heat transfer? (c) Make a graph of temperature versus time for this process.
79. In 1986, an enormous iceberg broke away from the Ross Ice Shelf in Antarctica. It was an approximately rectangular prism 160 km long, 40.0 km wide, and 250 m thick.
(a) What is the mass of this iceberg, given that the density of ice is \(917kg/m^3\)?
(b) How much heat transfer (in joules) is needed to melt it?
(c) How many years would it take sunlight alone to melt ice this thick, if the ice absorbs an average of \(100W/m^2\), 12.00 h per day?
80. How many grams of coffee must evaporate from 350 g of coffee in a 100-g glass cup to cool the coffee and the cup from 95.0°C to 45.0°C ? Assume the coffee has the same thermal properties as water and that the average heat of vaporization is 2340 kJ/kg (560 kcal/g). Neglect heat losses through processes other than evaporation, as well as the change in mass of the coffee as it cools. Do the latter two assumptions cause your answer to be higher or lower than the true answer?
81. (a) It is difficult to extinguish a fire on a crude oil tanker, because each liter of crude oil releases \(2.80×10^7J\) of energy when burned. To illustrate this difficulty, calculate the number of liters of water that must be expended to absorb the energy released by burning 1.00 L of crude oil, if the water’s temperature rises from 20.0°C to 100°C , it boils, and the resulting steam’s temperature rises to 300°C at constant pressure.
(b) Discuss additional complications caused by the fact that crude oil is less dense than water.
82. The energy released from condensation in thunderstorms can be very large. Calculate the energy released into the atmosphere for a small storm of radius 1 km, assuming that 1.0 cm of rain is precipitated uniformly over this area.
83 . To help prevent frost damage, 4.00 kg of water at 0°C is sprayed onto a fruit tree.
(a) How much heat transfer occurs as the water freezes?
(b) How much would the temperature of the 200-kg tree decrease if this amount of heat transferred from the tree? Take the specific heat to be 3.35kJ/kg⋅°C , and assume that no phase change occurs in the tree.
84. A 0.250-kg aluminum bowl holding 0.800kg of soup at 25.0°C is placed in a freezer. What is the final temperature if 388 kJ of energy is transferred from the bowl and soup, assuming the soup’s thermal properties are the same as that of water?
85. A 0.0500-kg ice cube at −30.0°C is placed in 0.400 kg of 35.0-°C water in a very well-insulated container. What is the final temperature?
86. If you pour 0.0100 kg of 20.0°C water onto a 1.20-kg block of ice (which is initially at −15.0°C ), what is the final temperature? You may assume that the water cools so rapidly that effects of the surroundings are negligible.
87. Indigenous people sometimes cook in watertight baskets by placing hot rocks into water to bring it to a boil. What mass of 500-°C granite must be placed in 4.00 kg of 15.0-°C water to bring its temperature to 100°C , if 0.0250 kg of water escapes as vapor from the initial sizzle? You may neglect the effects of the surroundings.
88. What would the final temperature of the pan and water be in Example 1.7 if 0.260 kg of water were placed in the pan and 0.0100 kg of the water evaporated immediately, leaving the remainder to come to a common temperature with the pan?
1.6: Mechanisms of Heat Transfer
89. (a) Calculate the rate of heat conduction through house walls that are 13.0 cm thick and have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The walls’ surface area is \(120m^2\) and their inside surface is at 18.0°C , while their outside surface is at 5.00°C .
(b) How many 1-kW room heaters would be needed to balance the heat transfer due to conduction?
90. The rate of heat conduction out of a window on a winter day is rapid enough to chill the air next to it. To see just how rapidly the windows transfer heat by conduction, calculate the rate of conduction in watts through a \(3.00-m^2\)window that is 0.634 cm thick (1/4 in.) if the temperatures of the inner and outer surfaces are 5.00°C and −10.0°C −, respectively. (This rapid rate will not be maintained—the inner surface will cool, even to the point of frost formation.)
91. Calculate the rate of heat conduction out of the human body, assuming that the core internal temperature is 37.0°C , the skin temperature is 34.0°C , the thickness of the fatty tissues between the core and the skin averages 1.00 cm, and the surface area is \(1.40m^2\).
92. Suppose you stand with one foot on ceramic flooring and one foot on a wool carpet, making contact over an area of \(80.0cm^2\) with each foot.  At what rate must heat transfer occur from each foot to keep the top of the ceramic and carpet at 33.0°C ?
93. A man consumes 3000 kcal of food in one day, converting most of it to thermal energy to maintain body temperature. If he loses half this energy by evaporating water (through breathing and sweating), how many kilograms of water evaporate?
94. A firewalker runs across a bed of hot coals without sustaining burns. Calculate the heat transferred by conduction into the sole of one foot of a firewalker given that the bottom of the foot is a 3.00-mm-thick callus with a conductivity at the low end of the range for wood and its density is \(300kg/m^3\). The area of contact is \(25.0cm^2\), the temperature of the coals is 700°C , and the time in contact is 1.00 s. Ignore the evaporative cooling of sweat.
95. (a) What is the rate of heat conduction through the 3.00-cm-thick fur of a large animal having a \(1.40-m^2\) surface area? Assume that the animal’s skin temperature is 32.0°C , that the air temperature is −5.00°C , and that fur has the same thermal conductivity as air.
(b) What food intake will the animal need in one day to replace this heat transfer?
96. A walrus transfers energy by conduction through its blubber at the rate of 150 W when immersed in −1.00°C water. The walrus’s internal core temperature is 37.0°C , and it has a surface area of \(2.00m^2\). What is the average thickness of its blubber, which has the conductivity of fatty tissues without blood?
97. Compare the rate of heat conduction through a 13.0-cm-thick wall that has an area of \(10.0m^2\) and a thermal conductivity twice that of glass wool with the rate of heat conduction through a 0.750-cm-thick window that has an area of \(2.00m^2\), assuming the same temperature difference across each.
98. Suppose a person is covered head to foot by wool clothing with average thickness of 2.00 cm and is transferring energy by conduction through the clothing at the rate of 50.0 W. What is the temperature difference across the clothing, given the surface area is \(1.40m^2\)?
99. Some stove tops are smooth ceramic for easy cleaning. If the ceramic is 0.600 cm thick and heat conduction occurs through the same area and at the same rate as computed in Example 1.11, what is the temperature difference across it? Ceramic has the same thermal conductivity as glass and brick.
100. One easy way to reduce heating (and cooling) costs is to add extra insulation in the attic of a house. Suppose a single-story cubical house already had 15 cm of fiberglass insulation in the attic and in all the exterior surfaces. If you added an extra 8.0 cm of fiberglass to the attic, by what percentage would the heating cost of the house drop? Take the house to have dimensions 10 m by 15 m by 3.0 m. Ignore air infiltration and heat loss through windows and doors, and assume that the interior is uniformly at one temperature and the exterior is uniformly at another.
101. Many decisions are made on the basis of the payback period: the time it will take through savings to equal the capital cost of an investment. Acceptable payback times depend upon the business or philosophy one has. (For some industries, a payback period is as small as 2 years.) Suppose you wish to install the extra insulation in the preceding problem. If energy cost $1.00 per million joules and the insulation was $4.00 per square meter, then calculate the simple payback time. Take the average ΔT for the 120-day heating season to be 15.0°C.
Additional Problems
102. In 1701, the Danish astronomer Ole Rømer proposed a temperature scale with two fixed points, freezing water at 7.5 degrees, and boiling water at 60.0 degrees. What is the boiling point of oxygen, 90.2 K, on the Rømer scale?
103. What is the percent error of thinking the melting point of tungsten is 3695°C instead of the correct value of 3695 K?
104. An engineer wants to design a structure in which the difference in length between a steel beam and an aluminum beam remains at 0.500 m regardless of temperature, for ordinary temperatures. What must the lengths of the beams be?
105. How much stress is created in a steel beam if its temperature changes from –15°C to 40°C but it cannot expand? For steel, the Young’s modulus \(Y=210×10^9N/m^2\) from Stress, Strain, and Elastic Modulus. (Ignore the change in area resulting from the expansion.)
106. A brass rod (\(Y=90×10^9N/m^2\)), with a diameter of 0.800 cm and a length of 1.20 m when the temperature is 25°C , is fixed at both ends. At what temperature is the force in it at 36,000 N?
107. A mercury thermometer still in use for meteorology has a bulb with a volume of \(0.780cm^3\) and a tube for the mercury to expand into of inside diameter 0.130 mm. (a) Neglecting the thermal expansion of the glass, what is the spacing between marks 1°C apart? (b) If the thermometer is made of ordinary glass (not a good idea), what is the spacing?
108. Even when shut down after a period of normal use, a large commercial nuclear reactor transfers thermal energy at the rate of 150 MW by the radioactive decay of fission products. This heat transfer causes a rapid increase in temperature if the cooling system fails ( 1watt=1joule/second or 1W=1J/ s and 1MW=1megawatt ).
(a) Calculate the rate of temperature increase in degrees Celsius per second ( °C/s ) if the mass of the reactor core is \(1.60×10^5kg\)and it has an average specific heat of 0.3349kJ/kg⋅°C .
(b) How long would it take to obtain a temperature increase of 2000°C , which could cause some metals holding the radioactive materials to melt? (The initial rate of temperature increase would be greater than that calculated here because the heat transfer is concentrated in a smaller mass. Later, however, the temperature increase would slow down because the 500,000-kg steel containment vessel would also begin to heat up.)
109. You leave a pastry in the refrigerator on a plate and ask your roommate to take it out before you get home so you can eat it at room temperature, the way you like it. Instead, your roommate plays video games for hours. When you return, you notice that the pastry is still cold, but the game console has become hot. Annoyed, and knowing that the pastry will not be good if it is microwaved, you warm up the pastry by unplugging the console and putting it in a clean trash bag (which acts as a perfect calorimeter) with the pastry on the plate. After a while, you find that the equilibrium temperature is a nice, warm 38.3°C . You know that the game console has a mass of 2.1 kg. Approximate it as having a uniform initial temperature of 45°C . The pastry has a mass of 0.16 kg and a specific heat of 3.0kJ/(kg⋅ºC), and is at a uniform initial temperature of 4.0°C . The plate is at the same temperature and has a mass of 0.24 kg and a specific heat of 0.90J/(kg⋅ºC) . What is the specific heat of the console?
110. Two solid spheres, A and B, made of the same material, are at temperatures of 0°C and 100°C , respectively. The spheres are placed in thermal contact in an ideal calorimeter, and they reach an equilibrium temperature of 20°C . Which is the bigger sphere? What is the ratio of their diameters?
111. In some countries, liquid nitrogen is used on dairy trucks instead of mechanical refrigerators. A 3.00-hour delivery trip requires 200 L of liquid nitrogen, which has a density of \(808kg/m^3.\).
(a) Calculate the heat transfer necessary to evaporate this amount of liquid nitrogen and raise its temperature to 3.00°C . (Use \(c_P\) and assume it is constant over the temperature range.) This value is the amount of cooling the liquid nitrogen supplies.
(b) What is this heat transfer rate in kilowatt-hours?
(c) Compare the amount of cooling obtained from melting an identical mass of 0-°C ice with that from evaporating the liquid nitrogen.
112. Some gun fanciers make their own bullets, which involves melting lead and casting it into lead slugs. How much heat transfer is needed to raise the temperature and melt 0.500 kg of lead, starting from 25.0°C ?
113. A 0.800-kg iron cylinder at a temperature of \(1.00×10^3°C\) is dropped into an insulated chest of 1.00 kg of ice at its melting point. What is the final temperature, and how much ice has melted?
114. Repeat the preceding problem with 2.00 kg of ice instead of 1.00 kg.
115. Repeat the preceding problem with 0.500 kg of ice, assuming that the ice is initially in a copper container of mass 1.50 kg in equilibrium with the ice.
116. A 30.0-g ice cube at its melting point is dropped into an aluminum calorimeter of mass 100.0 g in equilibrium at 24.0°C with 300.0 g of an unknown liquid. The final temperature is 4.0°C . What is the heat capacity of the liquid?
117. (a) Calculate the rate of heat conduction through a double-paned window that has a \(1.50-m^2\) area and is made of two panes of 0.800-cm-thick glass separated by a 1.00-cm air gap. The inside surface temperature is 15.0°C,15.0°C, while that on the outside is −10.0°C .( Hint: There are identical temperature drops across the two glass panes. First find these and then the temperature drop across the air gap. This problem ignores the increased heat transfer in the air gap due to convection.)
(b) Calculate the rate of heat conduction through a 1.60-cm-thick window of the same area and with the same temperatures. Compare your answer with that for part (a).
118. (a) An exterior wall of a house is 3 m tall and 10 m wide.  The wall is built so well that there are no leaks of air through it. When the inside of the wall is at 22°C and the outside is at −2°C , what is the rate of heat flow through the wall?
(b) More realistically, the 3.5-inch space also contains 2-by-4 studs—wooden boards 1.5 inches by 3.5 inches oriented so that 3.5-inch dimension extends from the drywall to the siding. They are “on 16-inch centers,” that is, the centers of the studs are 16 inches apart. What is the heat current in this situation? Don’t worry about one stud more or less.
119. For the human body, what is the rate of heat transfer by conduction through the body’s tissue with the following conditions: the tissue thickness is 3.00 cm, the difference in temperature is 2.00°C , and the skin area is1.50m21.50m2. How does this compare with the average heat transfer rate to the body resulting from an energy intake of about 2400 kcal per day? (No exercise is included.)
120. You have a Dewar flask (a laboratory vacuum flask) that has an open top and straight sides, as shown below. You fill it with water and put it into the freezer. It is effectively a perfect insulator, blocking all heat transfer, except on the top. After a time, ice forms on the surface of the water. The liquid water and the bottom surface of the ice, in contact with the liquid water, are at 0°C . The top surface of the ice is at the same temperature as the air in the freezer, −18°C . Set the rate of heat flow through the ice equal to the rate of loss of heat of fusion as the water freezes. When the ice layer is 0.700 cm thick, find the rate in m/s at which the ice is thickening.
121. An infrared heater for a sauna has a surface area of \(0.050m^2\) and an emissivity of 0.84. What temperature must it run at if the required power is 360 W? Neglect the temperature of the environment.
122. (a) Determine the power of radiation from the Sun by noting that the intensity of the radiation at the distance of Earth is \(1370W/m^2\. Hint: That intensity will be found everywhere on a spherical surface with radius equal to that of Earth’s orbit.
(b) Assuming that the Sun’s temperature is 5780 K and that its emissivity is 1, find its radius.
Challenge Problems
123. A pendulum is made of a rod of length L and negligible mass, but capable of thermal expansion, and a weight of negligible size.
(a) Show that when the temperature increases by dT, the period of the pendulum increases by a fraction αLdT/ 2 .
(b) A clock controlled by a brass pendulum keeps time correctly at 10°C. If the room temperature is 30°C , does the clock run faster or slower? What is its error in seconds per day?
124. At temperatures of a few hundred kelvins the specific heat capacity of copper approximately follows the empirical formula \(c=α+βT+δT^{−2}\), where α=349J/kg⋅K , \(β=0.107J/kg⋅K^2\), and \(δ=4.58×10^5J⋅kg⋅K\). How much heat is needed to raise the temperature of a 2.00-kg piece of copper from 20°C to 250°C ?
125. In a calorimeter of negligible heat capacity, 200 g of steam at 150°C and 100 g of ice at −40°C are mixed. The pressure is maintained at 1 atm. What is the final temperature, and how much steam, ice, and water are present?
126. An astronaut performing an extra-vehicular activity (space walk) shaded from the Sun is wearing a spacesuit that can be approximated as perfectly white (e=0) except for a 5cm×8cm patch in the form of the astronaut’s national flag. The patch has emissivity 0.300. The spacesuit under the patch is 0.500 cm thick, with a thermal conductivity k=0.0600W/m°C , and its inner surface is at a temperature of 20.0°C . What is the temperature of the patch, and what is the rate of heat loss through it? Assume the patch is so thin that its outer surface is at the same temperature as the outer surface of the spacesuit under it. Also assume the temperature of outer space is 0 K. You will get an equation that is very hard to solve in closed form, so you can solve it numerically with a graphing calculator, with software, or even by trial and error with a calculator.
127. The goal in this problem is to find the growth of an ice layer as a function of time. Call the thickness of the ice layer L.
(a) Derive an equation for dL/dt in terms of L , the temperature T above the ice, and the properties of ice (which you can leave in symbolic form instead of substituting the numbers).
(b) Solve this differential equation assuming that at t=0 , you have L=0 . If you have studied differential equations, you will know a technique for solving equations of this type: manipulate the equation to get dL/dt multiplied by a (very simple) function of L on one side, and integrate both sides with respect to time. Alternatively, you may be able to use your knowledge of the derivatives of various functions to guess the solution, which has a simple dependence on t.
(c) Will the water eventually freeze to the bottom of the flask?
128. As the very first rudiment of climatology, estimate the temperature of Earth. Assume it is a perfect sphere and its temperature is uniform. Ignore the greenhouse effect. Thermal radiation from the Sun has an intensity (the “solar constant” S) of about \(1370W/m^2\) at the radius of Earth’s orbit.
(a) Assuming the Sun’s rays are parallel, what area must S be multiplied by to get the total radiation intercepted by Earth? It will be easiest to answer in terms of Earth’s radius, R.
(b) Assume that Earth reflects about 30% of the solar energy it intercepts. In other words, Earth has an albedo with a value of A=0.3 . In terms of S, A, and R, what is the rate at which Earth absorbs energy from the Sun?
(c) Find the temperature at which Earth radiates energy at the same rate. Assume that at the infrared wavelengths where it radiates, the emissivity e is 1. Does your result show that the greenhouse effect is important?
(d) How does your answer depend on the the area of Earth?
129. Let’s stop ignoring the greenhouse effect and incorporate it into the previous problem in a very rough way. Assume the atmosphere is a single layer, a spherical shell around Earth, with an emissivity e=0.77 (chosen simply to give the right answer) at infrared wavelengths emitted by Earth and by the atmosphere. However, the atmosphere is transparent to the Sun’s radiation (that is, assume the radiation is at visible wavelengths with no infrared), so the Sun’s radiation reaches the surface. The greenhouse effect comes from the difference between the atmosphere’s transmission of visible light and its rather strong absorption of infrared. Note that the atmosphere’s radius is not significantly different from Earth’s, but since the atmosphere is a layer above Earth, it emits radiation both upward and downward, so it has twice Earth’s area. There are three radiative energy transfers in this problem: solar radiation absorbed by Earth’s surface; infrared radiation from the surface, which is absorbed by the atmosphere according to its emissivity; and infrared radiation from the atmosphere, half of which is absorbed by Earth and half of which goes out into space. Apply the method of the previous problem to get an equation for Earth’s surface and one for the atmosphere, and solve them for the two unknown temperatures, surface and atmosphere.
a. In terms of Earth’s radius, the constant σσ, and the unknown temperature \(T_s\) of the surface, what is the power of the infrared radiation from the surface?
b. What is the power of Earth’s radiation absorbed by the atmosphere?
c. In terms of the unknown temperature \(T_e\) of the atmosphere, what is the power radiated from the atmosphere?
d. Write an equation that says the power of the radiation the atmosphere absorbs from Earth equals the power of the radiation it emits.
e. Half of the power radiated by the atmosphere hits Earth. Write an equation that says that the power Earth absorbs from the atmosphere and the Sun equals the power that it emits.
f. Solve your two equations for the unknown temperature of Earth.
For steps that make this model less crude, see for example the lectures by Paul O’Gorman.


4.8: Conclusion
By the end of the 19 th century, changes were occurring around the world. Germany was emerging as the European industrial leader, building new factories and expanding its trade position. The United States was also exceptionally successful in expanding the country geographically and industrially, evolving as one of the wealthiest countries in the world. Across the globe, economies became interrelated as trade and integrated investments spread spurred by imperialism. Although Britain controlled the oceans and colonized multiple regions, its power began to ebb by the end of the century. Other European countries wanted natural resources like diamonds, gold, or oil and started establishing their ports and colonies in Asia and Africa, creating a competitive environment; when one state developed a settlement, another state established a small colony to lessen domination.
Interdependence across the continents grew from inventive transportation and communication systems and integrated trade policies. Inequities in different countries between the powerful and those controlled were based on armaments and military dominance, the railroad systems, medical advances, and raw industrial power. At the end of the century, the new international order in the world defined the primary status for the contemporary world of the 20 th century.


3.10: Substantive Law- Monetary Punishment Sentences
Monetary Punishments
Fines
The Model Penal Code proposed legislative guidelines on the use of fines, but states have generally rejected this provision. Instead, judges are given extremely broad discretion in setting the fine amounts, and there are few limits on the judge’s ability to impose a fine. Frequently, the criminal statute will specify the highest permissible fine. The Eighth Amendment’s Cruel and Unusual Punishment Clause prohibits excessive fines, but courts rarely have found a fine to violate this provision. In Tate v. Short , 401 U.S. 395 (1971), the Court found that fines that punish poor people more harshly than rich people, and thus, violate the Equal Protection Clause. Historically, magistrates had given offenders the option of paying a fine or serving a jail sentence. Sentences were frequently “thirty dollars or thirty days”. If defendants were too poor to pay the fine, they went to jail. The Tate Court reasoned that the state could imprison Tate for committing the crime, but by requiring either time or a fine, the state was really incarcerating Tate because he was too poor to pay the fine. After Tate , courts began using installment plans that permit poor defendants to pay fines over a period of several months. This practice may nonetheless subject the poor to an increased punishment if the court administration requires interest or some fee associated with a payment plan.
Civil Forfeiture
civil forfeiture, the process by which the government confiscates the proceeds (property or money) of criminal activities. See, 18 USCA §§981-982. Laws that allow the state to forfeit the property used in illicit drug activity are particularly controversial. In deciding whether forfeiture is legal, state courts generally look to constitutional provisions dealing with excessive fines. In Austin v. United States , 509 US 602, at 622 (1993), the Supreme Court said that civil forfeiture “constitutes payment to a sovereign as punishment for some offense’ . . . and, as such, is subject to the limitations of the Eighth Amendment’s Excessive Fines Clause.” However, the court left it to state and lower federal courts to determine the test of “excessiveness” in the context of forfeiture. The Illinois Supreme Court said that three factors should be considered in this regard: (1) the gravity of the offense relative to the value of the forfeiture, (2) whether the property was an integral part of the illicit activity, and (3) whether the illicit activity involving the property was extensive. [1] Federally, a $357,144 forfeiture for failing to report to U.S. Customs that more than $10,000 was being taken out of the country was found to be “grossly disproportionate” to the offense. [2] In one Pennsylvania case, the court found that forfeiture of a house used as a base of operations in an ongoing drug business was not excessive. [3]
United States v. Ursery 518 U.S. 267 (1996). On February 20th, 2019, the Court perhaps provided a different form of attack on civil forfeitures. In a unanimous opinion in Timbs v. Indiana, ___ U.S. ___ (2019) , Justice Ginsberg wrote that the Eighth Amendment’s excessive fines clause applies to the states as well as the federal government, and that when Indiana civilly forfeited Timbs’ $42,000 land rover after he sold a couple of hundred dollars worth of heroin, it was imposing an excessive fine.
United States v. James Daniel Good Real Property , 510 U.S. 43 (1993). Courts have found that civil forfeiture is constitutional even when the owner was not aware of the property’s criminal use. For example, in Bennis v. Michigan, 516 U.S. 442 (1996), the Court upheld the government’s seizure and forfeiture of Mrs. Bennis’s car, even though she claimed she did not know that her husband was using their car to engage in prostitution.
Link to http://www.osbar.org/publications/bulletin/06nov/forfeiture.html, for a discussion of the recent history of asset forfeiture in Oregon and the debate about Ballot Measure 3 and subsequent forfeiture cases and statutes.
Restitution and Compensatory Fines
Restitution refers to the “return of a sum of money, an object, or the value of an object that the defendant wrongfully obtained in the course of committing the crime.” [4] When the judge’s sentence includes restitution, the amount should be enough money to place the victim in the same position they would have been had the crime not been committed. Restitution orders can include the actual cost of destroyed property, medical bills, counseling fees, and lost wages. Several state laws require offenders to pay restitution as a condition of probation. Judges may order defendants to pay restitution for all damages incurred during a criminal episode, even if the charge is dismissed through negotiations. Judges may also order the defendant to pay restitution to some party other than the victim.
victims’ compensations commissions . Statewide, defendants make their restitution payments to these commissions that pay out restitution claims to victims across the state. Because of the statewide pot of money, victims can then get some, if not all, of what is needed to “make them whole.” Also, these commissions make it possible for the victim to get compensated without having to maintain contact with the offender.


29.7: The Evolution of Primates
Skills to Develop
- Describe the derived features that distinguish primates from other animals
- Explain why scientists are having difficulty determining the true lines of descent in hominids
Order Primates of class Mammalia includes lemurs, tarsiers, monkeys, apes, and humans. Non-human primates live primarily in the tropical or subtropical regions of South America, Africa, and Asia. They range in size from the mouse lemur at 30 grams (1 ounce) to the mountain gorilla at 200 kilograms (441 pounds). The characteristics and evolution of primates is of particular interest to us as it allows us to understand the evolution of our own species.
Characteristics of Primates
All primate species possess adaptations for climbing trees, as they all descended from tree-dwellers. This arboreal heritage of primates has resulted in hands and feet that are adapted for brachiation , or climbing and swinging through trees. These adaptations include, but are not limited to: 1) a rotating shoulder joint, 2) a big toe that is widely separated from the other toes and thumbs, which are widely separated from fingers (except humans), which allow for gripping branches, 3) stereoscopic vision , two overlapping fields of vision from the eyes, which allows for the perception of depth and gauging distance. Other characteristics of primates are brains that are larger than those of most other mammals, claws that have been modified into flattened nails, typically only one offspring per pregnancy, and a trend toward holding the body upright.
Order Primates is divided into two groups: prosimians and anthropoids. Prosimians include the bush babies of Africa, the lemurs of Madagascar, and the lorises, pottos, and tarsiers of Southeast Asia. Anthropoids include monkeys, apes, and humans. In general, prosimians tend to be nocturnal (in contrast to diurnal anthropoids) and exhibit a smaller size and smaller brain than anthropoids.
Evolution of Primates
The first primate-like mammals are referred to as proto-primates. They were roughly similar to squirrels and tree shrews in size and appearance. The existing fossil evidence (mostly from North Africa) is very fragmented. These proto-primates remain largely mysterious creatures until more fossil evidence becomes available. The oldest known primate-like mammals with a relatively robust fossil record is Plesiadapis (although some researchers do not agree that Plesiadapis was a proto-primate). Fossils of this primate have been dated to approximately 55 million years ago. Plesiadapiforms were proto-primates that had some features of the teeth and skeleton in common with true primates. They were found in North America and Europe in the Cenozoic and went extinct by the end of the Eocene.
The first true primates were found in North America, Europe, Asia, and Africa in the Eocene Epoch. These early primates resembled present-day prosimians such as lemurs. Evolutionary changes continued in these early primates, with larger brains and eyes, and smaller muzzles being the trend. By the end of the Eocene Epoch, many of the early prosimian species went extinct due either to cooler temperatures or competition from the first monkeys.
Anthropoid monkeys evolved from prosimians during the Oligocene Epoch. By 40 million years ago, evidence indicates that monkeys were present in the New World (South America) and the Old World (Africa and Asia). New World monkeys are also called Platyrrhini —a reference to their broad noses (Figure \(\PageIndex{1}\)). Old World monkeys are called Catarrhini —a reference to their narrow noses. There is still quite a bit of uncertainty about the origins of the New World monkeys. At the time the platyrrhines arose, the continents of South American and Africa had drifted apart. Therefore, it is thought that monkeys arose in the Old World and reached the New World either by drifting on log rafts or by crossing land bridges. Due to this reproductive isolation, New World monkeys and Old World monkeys underwent separate adaptive radiations over millions of years. The New World monkeys are all arboreal, whereas Old World monkeys include arboreal and ground-dwelling species.
Apes evolved from the catarrhines in Africa midway through the Cenozoic, approximately 25 million years ago. Apes are generally larger than monkeys and they do not possess a tail. All apes are capable of moving through trees, although many species spend most their time on the ground. Apes are more intelligent than monkeys, and they have relatively larger brains proportionate to body size. The apes are divided into two groups. The lesser apes comprise the family Hylobatidae , including gibbons and siamangs. The great apes include the genera Pan (chimpanzees and bonobos) (Figure \(\PageIndex{2}\)a), Gorilla (gorillas), Pongo (orangutans), and Homo (humans) (Figure \(\PageIndex{2}\)b). The very arboreal gibbons are smaller than the great apes; they have low sexual dimorphism (that is, the genders are not markedly different in size); and they have relatively longer arms used for swinging through trees.
Human Evolution
The family Hominidae of order Primates includes the hominoids : the great apes (Figure \(\PageIndex{3}\)). Evidence from the fossil record and from a comparison of human and chimpanzee DNA suggests that humans and chimpanzees diverged from a common hominoid ancestor approximately 6 million years ago. Several species evolved from the evolutionary branch that includes humans, although our species is the only surviving member. The term hominin is used to refer to those species that evolved after this split of the primate line, thereby designating species that are more closely related to humans than to chimpanzees. Hominins were predominantly bipedal and include those groups that likely gave rise to our species—including Australopithecus , Homo habilis , and Homo erectus —and those non-ancestral groups that can be considered “cousins” of modern humans, such as Neanderthals. Determining the true lines of descent in hominins is difficult. In years past, when relatively few hominin fossils had been recovered, some scientists believed that considering them in order, from oldest to youngest, would demonstrate the course of evolution from early hominins to modern humans. In the past several years, however, many new fossils have been found, and it is clear that there was often more than one species alive at any one time and that many of the fossils found (and species named) represent hominin species that died out and are not ancestral to modern humans.
Very Early Hominins
Three species of very early hominids have made news in the past few years. The oldest of these, Sahelanthropus tchadensis , has been dated to nearly 7 million years ago. There is a single specimen of this genus, a skull that was a surface find in Chad. The fossil, informally called “Toumai,” is a mosaic of primitive and evolved characteristics, and it is unclear how this fossil fits with the picture given by molecular data, namely that the line leading to modern humans and modern chimpanzees apparently bifurcated about 6 million years ago. It is not thought at this time that this species was an ancestor of modern humans.
A second, younger species, Orrorin tugenensis , is also a relatively recent discovery, found in 2000. There are several specimens of Orrorin . It is not known whether Orrorin was a human ancestor, but this possibility has not been ruled out. Some features of Orrorin are more similar to those of modern humans than are the australopiths, although Orrorin is much older.
A third genus, Ardipithecus , was discovered in the 1990s, and the scientists who discovered the first fossil found that some other scientists did not believe the organism to be a biped (thus, it would not be considered a hominid). In the intervening years, several more specimens of Ardipithecus , classified as two different species, demonstrated that the organism was bipedal. Again, the status of this genus as a human ancestor is uncertain.
Early Hominins: Genus Australopithecus
Australopithecus (“southern ape”) is a genus of hominin that evolved in eastern Africa approximately 4 million years ago and went extinct about 2 million years ago. This genus is of particular interest to us as it is thought that our genus, genus Homo , evolved from Australopithecus about 2 million years ago (after likely passing through some transitional states). Australopithecus had a number of characteristics that were more similar to the great apes than to modern humans. For example, sexual dimorphism was more exaggerated than in modern humans. Males were up to 50 percent larger than females, a ratio that is similar to that seen in modern gorillas and orangutans. In contrast, modern human males are approximately 15 to 20 percent larger than females. The brain size of Australopithecus relative to its body mass was also smaller than modern humans and more similar to that seen in the great apes. A key feature that Australopithecus had in common with modern humans was bipedalism, although it is likely that Australopithecus also spent time in trees. Hominin footprints, similar to those of modern humans, were found in Laetoli, Tanzania and dated to 3.6 million years ago. They showed that hominins at the time of Australopithecus were walking upright.
There were a number of Australopithecus species, which are often referred to as australopiths . Australopithecus anamensis lived about 4.2 million years ago. More is known about another early species, Australopithecus afarensis , which lived between 3.9 and 2.9 million years ago. This species demonstrates a trend in human evolution: the reduction of the dentition and jaw in size. A . afarensis (Figure \(\PageIndex{4}\)) had smaller canines and molars compared to apes, but these were larger than those of modern humans. Its brain size was 380–450 cubic centimeters, approximately the size of a modern chimpanzee brain. It also had prognathic jaws , which is a relatively longer jaw than that of modern humans. In the mid-1970s, the fossil of an adult female A . afarensis was found in the Afar region of Ethiopia and dated to 3.24 million years ago (Figure \(\PageIndex{5}\)). The fossil, which is informally called “Lucy,” is significant because it was the most complete australopith fossil found, with 40 percent of the skeleton recovered.
Australopithecus africanus lived between 2 and 3 million years ago. It had a slender build and was bipedal, but had robust arm bones and, like other early hominids, may have spent significant time in trees. Its brain was larger than that of A . afarensis at 500 cubic centimeters, which is slightly less than one-third the size of modern human brains. Two other species, Australopithecus bahrelghazali and Australopithecus garhi , have been added to the roster of australopiths in recent years.
A Dead End: Genus Paranthropus
The australopiths had a relatively slender build and teeth that were suited for soft food. In the past several years, fossils of hominids of a different body type have been found and dated to approximately 2.5 million years ago. These hominids, of the genus Paranthropus , were relatively large and had large grinding teeth. Their molars showed heavy wear, suggesting that they had a coarse and fibrous vegetarian diet as opposed to the partially carnivorous diet of the australopiths. Paranthropus includes Paranthropus robustus of South Africa, and Paranthropus aethiopicus and Paranthropus boisei of East Africa. The hominids in this genus went extinct more than 1 million years ago and are not thought to be ancestral to modern humans, but rather members of an evolutionary branch on the hominin tree that left no descendants.
Early Hominins: Genus Homo
The human genus, Homo , first appeared between 2.5 and 3 million years ago. For many years, fossils of a species called H . habilis were the oldest examples in the genus Homo , but in 2010, a new species called Homo gautengensis was discovered and may be older. Compared to A . africanus , H . habilis had a number of features more similar to modern humans. H . habilis had a jaw that was less prognathic than the australopiths and a larger brain, at 600–750 cubic centimeters. However, H . habilis retained some features of older hominin species, such as long arms. The name H . habilis means “handy man,” which is a reference to the stone tools that have been found with its remains.
Link to Learning
Visit this site for a video about Smithsonian paleontologist Briana Pobiner explaining the link between hominin eating of meat and evolutionary trends.
H . erectus appeared approximately 1.8 million years ago (Figure \(\PageIndex{6}\)). It is believed to have originated in East Africa and was the first hominin species to migrate out of Africa. Fossils of H . erectus have been found in India, China, Java, and Europe, and were known in the past as “Java Man” or “Peking Man.” H . erectus had a number of features that were more similar to modern humans than those of H . habilis . H . erectus was larger in size than earlier hominins, reaching heights up to 1.85 meters and weighing up to 65 kilograms, which are sizes similar to those of modern humans. Its degree of sexual dimorphism was less than earlier species, with males being 20 to 30 percent larger than females, which is close to the size difference seen in our species. H . erectus had a larger brain than earlier species at 775–1,100 cubic centimeters, which compares to the 1,130–1,260 cubic centimeters seen in modern human brains. H . erectus also had a nose with downward-facing nostrils similar to modern humans, rather than the forward facing nostrils found in other primates. Longer, downward-facing nostrils allow for the warming of cold air before it enters the lungs and may have been an adaptation to colder climates. Artifacts found with fossils of H . erectus suggest that it was the first hominin to use fire, hunt, and have a home base. H . erectus is generally thought to have lived until about 50,000 years ago.
Humans: Homo sapiens
A number of species, sometimes called archaic Homo sapiens , apparently evolved from H . erectus starting about 500,000 years ago. These species include Homo heidelbergensis , Homo rhodesiensis , and Homo neanderthalensis . These archaic H . sapiens had a brain size similar to that of modern humans, averaging 1,200–1,400 cubic centimeters. They differed from modern humans by having a thick skull, a prominent brow ridge, and a receding chin. Some of these species survived until 30,000–10,000 years ago, overlapping with modern humans (Figure \(\PageIndex{7}\)).
There is considerable debate about the origins of anatomically modern humans or Homo sapiens sapiens . As discussed earlier, H . erectus migrated out of Africa and into Asia and Europe in the first major wave of migration about 1.5 million years ago. It is thought that modern humans arose in Africa from H . erectus and migrated out of Africa about 100,000 years ago in a second major migration wave. Then, modern humans replaced H . erectus species that had migrated into Asia and Europe in the first wave.
This evolutionary timeline is supported by molecular evidence. One approach to studying the origins of modern humans is to examine mitochondrial DNA (mtDNA) from populations around the world. Because a fetus develops from an egg containing its mother’s mitochondria (which have their own, non-nuclear DNA), mtDNA is passed entirely through the maternal line. Mutations in mtDNA can now be used to estimate the timeline of genetic divergence. The resulting evidence suggests that all modern humans have mtDNA inherited from a common ancestor that lived in Africa about 160,000 years ago. Another approach to the molecular understanding of human evolution is to examine the Y chromosome, which is passed from father to son. This evidence suggests that all men today inherited a Y chromosome from a male that lived in Africa about 140,000 years ago.
Summary
All primate species possess adaptations for climbing trees, as they all probably descended from tree-dwellers, although not all species are arboreal. Other characteristics of primates are brains that are larger than those of other mammals, claws that have been modified into flattened nails, typically only one young per pregnancy, stereoscopic vision, and a trend toward holding the body upright. Primates are divided into two groups: prosimians and anthropoids. Monkeys evolved from prosimians during the Oligocene Epoch. Apes evolved from catarrhines in Africa during the Miocene Epoch. Apes are divided into the lesser apes and the greater apes. Hominins include those groups that gave rise to our species, such as Australopithecus and H . erectus , and those groups that can be considered “cousins” of humans, such as Neanderthals. Fossil evidence shows that hominins at the time of Australopithecus were walking upright, the first evidence of bipedal hominins. A number of species, sometimes called archaic H . sapiens , evolved from H . erectus approximately 500,000 years ago. There is considerable debate about the origins of anatomically modern humans or H . sapiens sapiens .
Glossary
- anthropoid
- monkeys, apes, and humans
- Australopithecus
- genus of hominins that evolved in eastern Africa approximately 4 million years ago
- brachiation
- movement through trees branches via suspension from the arms
- Catarrhini
- clade of Old World monkeys
- Gorilla
- genus of gorillas
- hominin
- species that are more closely related to humans than chimpanzees
- hominoid
- pertaining to great apes and humans
- Homo
- genus of humans
- Homo sapiens sapiens
- anatomically modern humans
- Hylobatidae
- family of gibbons
- Pan
- genus of chimpanzees and bonobos
- Platyrrhini
- clade of New World monkeys
- Plesiadapis
- oldest known primate-like mammal
- Pongo
- genus of orangutans
- Primates
- order of lemurs, tarsiers, monkeys, apes, and humans
- prognathic jaw
- long jaw
- prosimian
- division of primates that includes bush babies of Africa, lemurs of Madagascar, and lorises, pottos, and tarsiers of Southeast Asia
- stereoscopic vision
- two overlapping fields of vision from the eyes that produces depth perception


11.3.5: What to Do in a Serious Medical Emergency
Should a serious medical emergency occur, Home Health Aides/Personal Care Aides should assess the situation using their observational senses. Note what is seen, heard, felt, and smelled. Immediately call for help. Activate emergency medical services (EMS) by dialing 911. Inform them in a calm and matter of fact way what occurred and the observations made. Never leave the victim unattended.
ABCs of First Aid
Keep in mind the ABCs of first aid. The ABCs of first aid stand for A ( Airway ), B ( Breathing ), and C ( Circulation ) . It is important to remember this acronym as any delay in treatment when a patient has a compromised airway, breathing, or circulation could result in serious injury, and possibly death.
Assessing the ABCs:
Airway
- Is the patient’s airway ( mouth , nose), open?
- Is there an obstruction which makes it impossible for them to breathe?
- If there is an obstruction and the person is unable to breathe, activate EMS and perform the Heimlich maneuver to try to remove the obstruction.
Breathing
- Is the person breathing?
- Can you see the chest rise and fall as they breathe?
- Can you feel air move in and out of their mouth or nose?
- If the answer is no to any of these questions, Home Health Aides/Personal Care Aides should activate EMS and begin CPR if trained to do so . Hands-only CPR can be performed if you are not trained in CPR.
Circulation
- Do they have a pulse?
- How is their color? Are they blue from lack of oxygen?
- Does their skin feel warm to the touch or cold? Cold skin means not enough blood is pumping through the body.
- If the person does not have a pulse, Home Health Aides/Personal Care Aides should activate EMS and perform CPR if trained to do so .
Take note of the ABCs of first aid. Activate emergency medical services if any of the ABCs are compromised. Report your observations to EMS. Stay with the patient. If trained , perform CPR.