21.1: Magnetic fields
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Just as we can model the electric force on a charge by using the electric field (e.g. from another charge), we can model the force on a magnet by using a magnetic field (e.g. from another magnet). In your experience, every magnet that you have seen always has a “North” pole and a “South” pole. Most likely, you have noticed that the North pole of a magnet is attracted to the South pole of another magnet, and that the two North (or South) poles of different magnets repel each other. Thus, the magnetic force is attractive between two opposite poles, and repulsive otherwise.
The Earth itself can be modeled as a giant bar magnet, with North and South magnetic poles. The poles on a magnet are labeled North and South according to which geographic pole of the Earth they are attracted to (a magnetic compass needle has a magnetic North pole on the side that point to the Earth’s North geographic pole).
Exercise \(\PageIndex{1}\)
Is the magnetic North pole of the Earth located closer to the Earth’s geographic North pole or closer to its geographic South Pole?
- Earth does not have a magnetic field.
- Earth’s magnetic North pole is at Earth’s geographic North pole.
- Earth’s magnetic North pole is at Earth’s geographic South pole.
- Earth’s magnetic North pole depends on the charge of the observer.
- Answer
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It may seem that the magnetic force can be described in the same way as the electric force, having two opposite sign “charges” (or poles for magnets), although this is not the case. As far as we can tell, there are no magnets that have only a North or a South pole. Every magnet must have a North and a South pole. This is fundamentally different from the electric force, where an object can have a net positive or negative charge. In the context of magnetism, we say that “monopoles do not exist” (an object that has only a North or a South pole would be called a monopole). This is illustrated in Figure \(\PageIndex{1}\), which shows what happens as one cuts a bar magnet into two pieces; rather than ending up with a North and a South piece (monopoles), we end up with two smaller bar magnets, each with their own North and South poles, and so on if we try to subdivide the magnets further.
We model the magnetic force using a magnetic field vector, usually labeled, \(\vec B\) . The magnitude of the magnetic field has the S.I. units of Teslas (\(\text{T}\)). We draw magnetic field lines in much the same way that we draw electric field lines. The magnetic field lines are such that the magnetic field vector, \(\vec B\) , at some point in space is tangent to the field line at that point. The strength of the magnetic field is determined by the density of field lines at that position in space. The direction of the magnetic field, \(\vec B\) , indicates the direction of the force that is exerted on the North pole of a magnet. Magnetic field lines thus flow away from North poles and towards South poles.
The magnetic field description is similar to that of the electric field, with North magnetic poles being similar to positive electric charges, and vice versa. However, because magnetic monopoles do not exist, magnetic field lines do not end (or start) on the pole of a magnet. Rather, magnetic field lines must always form closed loops . Figure \(\PageIndex{2}\) shows the magnetic field lines for a bar magnet, highlighting that the field lines do not end at the poles, but rather continue through the magnet (and some of the lines only “close” outside of the figure). The magnetic field from a bar magnet is very similar to the electric field created by an electric dipole (and for that reason, we often use the term magnetic dipole to describe objects that create a magnetic field with the same shape).
We will discuss how to model magnetic fields in the next chapter, but it is important to understand that magnetic fields are created by moving electric charges. The electrons in the material that forms a bar magnet are the moving charges that create the magnetic field. As we will see, the magnetic field from a charge moving around in a circle (or a circular loop of current), has exactly the same shape as that of a bar magnet, as illustrated in Figure \(\PageIndex{3}\). We can thus think of charge moving in a circle as a small bar magnet, or more precisely, as a magnetic dipole.
In a magnet, the electrons in the material are moving in such a way that the magnetic fields that they generate are all in the same direction. Each atom is like a small magnetic dipole, and all of these are aligned. This allows us to understand why cutting a magnet does not result in two monopoles (Figure \(\PageIndex{1}\)): when we cut the bar magnet, we end up with less material, but each piece of material still contains magnetic dipoles that are aligned with each other, each having a North and South side. Note that it is not the motion of electrons around their nuclei that results in the magnetic field, and that one requires quantum mechanics and the notion of “spin” to describe this all in detail.
Most materials will respond to magnetic fields, but the behavior is most evident in “ferromagnetic” materials, such as iron (Fe). Ferromagnetic materials can be magnetized by an external magnetic field, effectively transforming them into magnets. One can think of a material as containing many little magnetic dipoles (from the motion of the electrons), which themselves are like bar magnets. If that material is ferromagnetic, an external magnetic field can act on the little “bar magnets”, orienting them all in the same way, so that the material as a whole becomes magnetic. For some ferromagnetic materials, that common orientation will remain when the external magnetic field is removed, creating a “permanent magnet”. For other ferromagnetic materials, the common orientation disappears when the external field is removed; those materials are thus attracted to a magnet, but they cannot form a magnet.


27.5: People with Disabilities
By the end of this section, you should be able to:
- Define disability.
- Describe the health barriers individuals with disabilities face.
- Discuss the health needs of the population of individuals with disabilities.
- Examine how the health needs of individuals with disabilities intersect with the social determinants of health.
- Identify the nurse’s role in caring for individuals with disabilities.
Individuals with disabilities make up a large minority group in the United States, with over 61 million individuals (approximately one in four people) affected (CDC, 2020g). Disabilities occur across all ages, genders, and racial, ethnic, and social groups. The WHO describes disability as an “interaction between an individual’s functional impairments or chronic health conditions and the physical and social environment” (Mitra et al., 2022, p. 1380). In contrast, the medical model often defines disability as an impairment in a person’s body or mind that results in difficulty doing certain activities and interacting with the environment around them (CDC, 2020e). There are many types of disabilities affecting vision, movement, thinking, remembering, learning, communicating, hearing, mental health, and social relationships (CDC, 2020e).
Institutional discrimination , lack of disability cultural competency in health professional curricula, and systemic barriers in the health care system result in significant health disparities between individuals experiencing disabilities and those who are not (National Council on Disability [NCD], n.d.). Health disparities for individuals with disabilities who are BIPOC or living in rural areas are even more significant (Crankshaw, 2023; Steinweg, 2023). Despite the Americans with Disabilities Act (ADA) of 1990 and the Amendments Act of 2008, which mandate equal access to health care services, disparities result from physical inaccessibility of health care settings, inadequate accommodations for communication, ableist discrimination, and implicit and explicit biases among health care staff (Lagu et al., 2022). Ableism is the intentional or unintentional discrimination against individuals with disabilities (National Conference for Community and Justice [NCCJ], 2021). This population often experiences unaccommodating health care settings and substandard care. Discriminatory attitudes among health care staff perpetuate health disparities and discourage individuals with disabilities from seeking care (Lagu et al., 2022).
Many Healthy People 2030 objectives relate to improving the health and well-being of individuals with disabilities . These objectives highlight the importance of promoting the health and well-being of all individuals, regardless of ability, to reduce health disparities and achieve health equity. Recall that health disparities are preventable differences in health between groups of individuals, usually due to social or economic factors, geographic location, environment, or ability.
Health Barriers Experienced by Individuals with Disabilities
Individuals with disabilities face frequent barriers to optimal and equitable care, including an inaccessible physical environment, a lack of assistive technology for communication, a lack of understanding, and negative attitudes.
Many physical barriers may prevent individuals from obtaining health care. Individuals with mobility disorders may have difficulty accessing health care facilities due to unaccommodating sidewalks, curbs, and stairs. Inside the building, stairs, small rooms, immobile exam tables, and standing scales that do not accommodate wheelchairs are additional barriers. ADA regulations for equitable or accessible physical spaces relate only to fixed structures and do not include medical equipment, furnishings, or diagnostic equipment (Iezonni et al., 2022). For example, a lack of accessible equipment for routine Pap smear screening and mammography screening is common (CDC, 2020a). While hospitals may be more likely to have appropriate equipment for individuals with disabilities, most private health care professional offices and outpatient facilities do not (Iezonni et al., 2022).
Negative attitudes toward individuals with disabilities impact health care encounters and contribute to disparities in health outcomes. Data from implicit attitude testing among health care professionals across all disciplines has revealed a pervasive ableist bias (Iezonni et al., 2022). In a 2019–2020 national survey, more than 80 percent of outpatient physicians felt that individuals with significant disability have worse quality of life than nondisabled individuals, and only 40 percent thought they could provide the same quality of care to clients with disability as they do to those without (Iezonni et al., 2022). These assumptions affect the quality of care this population receives. Health professionals often fail to ask appropriate health screening questions or to actively listen to these clients (CDC, 2020a). For example, in one study health care providers did not ask clients with disabilities about sexual activity and therefore failed to screen them appropriately for human papillomavirus and cervical cancer (Iezonni et al., 2022). By stereotyping individuals with disabilities as being unhealthy or having a poor quality of life, nurses and other health care professionals perpetuate stigma and health care disparities.
Another barrier experienced by individuals with disabilities is the lack of person-first language. Instead, the language focuses on the disability versus ability. Person-first language refers to people first to separate the person from a diagnosis or impairment (Crocker & Smith, 2019). An example is referring to a group of children as "children with intellectual disabilities" versus "intellectually disabled children" or referring to "clients with sensory disorders" rather than "sensory disorder clients". The goal is to focus more on the person rather than the diagnosis to decrease the stigma of a disability or condition. It also contradicts the mindset that everyone with a certain diagnosis is the same (Crocker & Smith, 2019). There is also a push toward identity-first language that views the individual’s disability as a large part of that person’s identity. For example, the Deaf community is opposed to person-first language as they view deafness as a medical condition that should not be stigmatized (Crocker & Smith, 2019). While person-first language is often taught in health care programs, it is often not used in the clinical setting, creating another barrier for clients with disabilities (Crocker & Smith, 2019).
If nurses and other health care providers do not receive adequate training to practice culturally sensitive care to clients with disabilities, this creates a barrier to care. In this video, Melissa Crisp-Cooper shares her health care experiences as an individual with a disability.
Watch the video, and then respond to the following questions.
- What are some barriers to receiving quality health care Melissa experienced?
- What are some potential strategies to mitigate these barriers?
- How can the community health nurse address disparities in caring for individuals with disabilities?
The CDC describes communication, programmatic, social, and transportation as other common barriers making it difficult for individuals with disabilities to function.
Communication Barriers
The ADA requires local and state governments, businesses, and nonprofits serving the public to communicate effectively with individuals who have communication disabilities (ADA.gov, 2020). Although it is an ADA violation for businesses to require clients to bring another person to interpret or assist in communication (ADA.gov, 2020), many health care providers do not accommodate alternative communication styles. In a large study, physicians reported relying on clients’ caregivers to overcome communication barriers and often communicating solely with the caregiver, leaving the client with the disability out of the conversation completely (Lagu et al., 2022). These physicians reported cost and time commitment as challenges to accommodating this population’s communication needs (Lagu et al., 2022). Many outpatient providers allot 15 minutes for a client visit, but they may need more time to accommodate alternate means of communication, including working with interpreters and providing health promotion education materials in large print, Braille, or versions made for screen readers (CDC, 2020a). Some auditory messages, such as oral communication or videos, can be inaccessible for individuals with hearing impairments without American Sign Language interpretation or captioning (CDC, 2020a).
Programmatic Barriers
Programmatic barriers include a lack of accessible equipment or adequate time for medical examinations, inopportune scheduling, and providers’ attitudes, knowledge, and understanding of people with disabilities (CDC, 2020a). As discussed previously, there are many physical barriers to accessing quality care, including access to equipment. Clients with disabilities that affect mobility, hearing, seeing, or cognition may require more time for a quality health encounter. Given current reimbursement models and the push to see a certain number of clients per hour, the lack of adequate time for examination is burdensome to many providers (Lagu et al., 2022).
Social and Transportation Barriers
Social barriers to care refer to those SDOH that adversely affect health outcomes. Individuals with disabilities are less likely to have completed high school or be employed and are more likely to have low income levels (CDC, 2020a), placing them at increased risk for economic insecurity, greater adversity, higher levels of chronic stress, and ultimately poorer health outcomes. Additionally, children with disabilities are four times more likely to experience violence, another factor impacting overall poor health (CDC, 2020a). This population may face transportation barriers, including a lack of access to transportation for individuals who cannot drive due to vision, cognitive, or mobility impairments (Figure 27.7) (CDC, 2020a). Economic insecurity may limit access to a private vehicle for those who can drive. Health visits can become less of a priority without easy access to transportation.
Health Needs of Individuals with Disabilities
In the United States, individuals with disabilities are three times as likely as individuals without disabilities to have arthritis, diabetes, and a heart attack and five times as likely to report a stroke, chronic obstructive pulmonary disease (COPD), and depression (NCD, 2023). Individuals living with disabilities are more likely to be obese and have unmet medical and dental needs. Women with disabilities often are not referred for routine pap smears and mammography, and pregnant clients with disabilities have 11 times the risk of maternal death of those without disabilities (NCD, 2023).
This population is at greater risk for victimization —purposely perpetrated violence and abuse—than nondisabled individuals. Victimization commonly occurs at home and in hospitals and includes physical and sexual violence, emotional abuse, and neglect of personal needs, medical care, or equipment. Almost 12 percent of adults with a disability were victims of sexual assault compared to 4 percent of adults without a disability (CDC, 2020f). Children with disabilities are more than twice as likely to be physically or sexually abused as children without disabilities (CDC, 2020d). At every health care encounter, these individuals should be screened appropriately for abuse and treated with a trauma-informed lens. Trauma-informed care is an approach to providing clinical care that encourages a culture of safety, empowerment, and healing for clients (Rittenberg, 2018). For individuals who have experienced sexual assault, victimization, or any other trauma, experiences in a health care facility where they are asked sensitive questions, told to remove clothing, undergo invasive testing, or perceive an overall differential in power can be frightening (Rittenberg, 2018). Using a trauma-informed lens means the nurse and health care provider work together to explain why they are asking certain questions or performing certain exams, taking the time to build a rapport with the client. See Caring for Populations and Communities in Crisis for more information on trauma-informed care.
Individuals with disabilities are more likely to report having overall poorer health and engaging in risky health behaviors such as smoking and physical inactivity than individuals without disabilities (CDC, 2020c). Obesity is more common in children and adults with mobility limitations and intellectual disabilities, resulting in potentially serious health consequences of metabolic syndrome, heart disease, and diabetes (CDC, 2019b). This population may be more vulnerable to preventable health problems and may experience secondary conditions such as pain and fatigue because of their disabling condition.
In addition to poorer physical health, individuals with disabilities report much higher rates of stress and depression than nondisabled individuals (CDC, 2020d). The good news is that many of this population’s health needs are preventable, so health care providers and nurses can intervene at a primary prevention level to effect meaningful change for these clients. With this high-risk group, nurses must consistently apply the many evidence-based strategies to combat smoking and physical inactivity.
How Individuals with Disabilities Intersect with the Social Determinants of Health
The health needs of individuals with disabilities intersect with the SDOH, as other forms of marginalization affect the health disparities among this population (Mitra et al., 2022). Transgender adults have much higher rates of disability compared with cisgender men and women, leading some to consider disability from an intersectionality lens—that is, to consider the intersection of disability with other categories of disadvantage such as gender identity, age, and racial and ethnic status (Smith-Johnson, 2022).
In 2018, more than a quarter of individuals with disabilities in the United States lived below the federal poverty level , compared with 10 percent of the nondisabled population (Semega et al., 2021). Poverty is often the result of unemployment, poor educational access, and discrimination (Engelman et al., 2022). Engaging in meaningful work is an essential aspect of a healthy, economically stable adulthood. Unemployment or inability to work is often associated with economic insecurity and poverty, resulting in direct adverse determinants of health. Across all age groups, individuals with a disability are much less likely to be employed, with an unemployment rate twice as high in this population as in that of their nondisabled counterparts (U.S. Bureau of Labor Statistics, 2023).
A person’s neighborhood can positively or negatively impact their health. For example, a neighborhood’s “walkability” affects the physical mobility of walkers and those with mobility difficulties who are at increased risk for many chronic diseases for which inactivity is a risk factor. Adults with disabilities perceive fewer neighborhood environmental supports and more barriers to walking than their nondisabled counterparts (Omura et al., 2020). Barriers to walkability include a lack of sidewalks, safe walking paths, and curb outlets for wheelchairs.
Like other historically marginalized populations with lower socioeconomic positions, this population is disproportionately affected by environmental conditions like climate change and extreme weather. For example, heat waves adversely impact individuals with spinal cord injuries, diabetes, heart disease, and other neurological conditions (Engelman et al., 2022). While air conditioning helps, not everyone can afford it or the electricity associated with its use. Cooling centers may be inaccessible due to distance, transportation issues, medical conditions, and facility barriers. This is the intersection between disability, lack of employment, and poverty (Engelman et al., 2022).
The Nurse’s Role in Caring for Individuals with Disabilities
The role of the community and public health nurse in caring for individuals with disabilities spans the three core functions of public health nursing: assessment, policy development, and assurance. The public health nurse should assess their community’s health needs and collect and trend data on the health outcomes of vulnerable populations. Using this data, nurses can appropriately educate health care professionals, organizations, businesses, and clients and devise effective policies to address health care issues and gaps. The public health nurse should then follow up to ensure policies are being implemented.
The inclusion of individuals with disabilities in society involves removing barriers that inhibit their full participation and requires a multifaceted approach that includes (CDC, 2020b):
- Addressing discrimination to allow all individuals to access fair treatment
- Using universal design to make the physical environment and communication space accessible to as many people as possible
- Working to eliminate stigma and stereotypes associated with disabilities
- Providing reasonable accommodations
Additionally, nurses should market community health programs to everyone, including individuals with disabilities. These individuals need these programs, just like everyone else, to engage with and be a part of the community.


14.4: Kinetic vs. Thermodynamic Control of Reactions
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Objectives
After completing this section, you should be able to
- explain the difference between thermodynamic and kinetic control of a chemical reaction; for example, the reaction of a conjugated diene with one equivalent of hydrogen halide.
- draw a reaction energy diagram for a reaction which can result in both a thermodynamically controlled product and a kinetically controlled product.
- explain how reaction conditions can determine the product ratio in a reaction in which there is competition between thermodynamic and kinetic control.
Key Terms
Make certain that you can define, and use in context, the key terms below.
- kinetic control
- thermodynamic control
Like non-conjugated dienes, conjugated dienes are subject to attack by electrophiles. In fact, conjugated dienes experience relatively greater kinetic reactivity when reacted with electrophiles than non-conjugated dienes do. The reaction mechanism is similar to other electrophilic addition reactions to alkenes (Section 7.9) . During the electrophilic addition of HBr to a 1,3-butadiene, However, there are two possible outcomes once the carbocation intermediate is formed. The allyl carbocation is stabilized by resonance structures that vary in the position of the carbocation. This allows the bromide ion to add to either of these carbons resulting in the formation 1,2 and 1,4 addition products. When this reaction is run at a temperature of 0 o C or lower, the 1,2 addition product dominates. However, if the same reaction is run at 40 o C the 1,4 addition product dominates.
The reaction of one equivalent of hydrogen bromide with 1,3-butadiene yields different product ratios under different reaction conditions and is a classic example of the concept of thermodynamic versus kinetic control of a reaction.
At lower temperatures the formation of the 1,2 and 1,4 addition products are irreversible and thus do not reach equilibrium. When a reaction is irreversible the major product is determined by the relative reaction rates and not by thermodynamic stability. Of the two products, the formation of the 1,2 addition product has a higher rate of reaction and forms faster making it the major product. The reaction product which forms with a higher rate of reaction is called the Kinetic Product and when the kinetic product dominates, the reaction is said to be under Kinetic Control .
At higher temperatures the reaction to form both products becomes reversible and a reaction equilibrium is reached. When a reaction is reversible the major product is determined by thermodynamic stability. The 1,4 addition product is more stable and becomes the major product under these reaction conditions. The more stable product is called the Thermodynamic Product and when the thermodynamic product dominates, the reaction is said to be under Thermodynamic Control .
The 1,4 addition product is more stable because it has an internal, disubstituted double bond, and we know that as a general rule that the thermodynamic stability of an alkene increases with increasing substitution. So, when compared to the terminal, monosubstituted alkene of the 1,2 addition product, the 1,4 addition product is expected to be more stable.
A simple definition is that the kinetic product is the product that is formed faster , and the thermodynamic product is the product that is more stable . This is precisely what is happening here. The kinetic product is 3-bromobut-1-ene, and the thermodynamic product is 1-bromobut-2-ene (specifically, the trans isomer).
An explanation for the temperature influence is shown in the following energy diagram for the addition of HBr to 1,3-butadiene. The initial step in which a proton bonds to carbon #1 is the rate determining step , as indicated by the large activation energy (light gray arrow). The second faster step is the product determining step , and there are two reaction paths (colored blue for 1,2-addition and magenta for 1,4-addition).
At elevated temperatures, the products are more likely to have enough energy to overcome the reverse activation barrier for the second step allowing regeneration of the carbocation intermediate. Under these conditions, this step of the mechanism will be reversible and an equilibrium will be established. Since the system is no longer limited by temperature, the system will minimize its Gibbs free energy, which is the thermodynamic criterion for chemical equilibrium. This places the reaction under thermodynamic control and the most thermodynamically stable molecule, the 1,4 addition product, will be predominantly formed.
If the reaction temperature is kept sufficiently low , the products will not have enough energy to overcome the reverse activation barrier to regenerate the carbocation intermediate making this step of the mechanism effectively irreversible. This reaction is under kinetic control meaning the product which forms faster, the kinetic product, will predominate.
Of the two reaction pathways, the 1,2-addition has a smaller activation energy and would be expected to have a higher reaction rate than the 1,4-addition. The high reaction rate for 1,2-addition can be attributed to the formation of an ion pair during the reaction mechanism. This means that, after a double bond is protonated, the halide counterion remains in close proximity to the carbocation generated. Immediately following dissociation of HX, the chloride ion is going to be much closer to C−2 than it is to C−4, and therefore attack at C−2 is much faster. This ion pair mechanism is a pre-exponential constant effects that is attributed to the proximity and frequency of collision rather than a activation barrier effect.
Experimental Evidence for the Ion-Pair Mechanism
In 1979, Nordlander et al. carried out a similar investigation on the addition of DCl (deuterated hydrochloric acid) to a different substrate, 1,3-pentadiene. This experiment was ingenious, because it was designed to proceed via an almost symmetrical intermediate:
Resonance forms 7a and 7b are both allylic and secondary. There is a very minor difference in their stabilities arising from the different hyperconjugative ability of C-D vs C-H bonds, but in any case, it is not very large. Therefore, if we adopt the explanation in the previous section, one would expect there not to be any major kinetic pathway, and both 1,2- and 1,4-addition products ( 8 and 9 ) would theoretically be formed roughly equally.
Instead, it was found that the 1,2-addition product was favored over the 1,4-addition product. For example, at -78 o C in the absence of solvent, there was a roughly (75:25) ratio of 1,2- to 1,4-addition products. Clearly, there is a factor that favors 1,2-addition that does not depend on the electrophilicity of the carbon being attacked! The authors attributed this effect to an ion pair mechanism. This means that, after the double bond is protonated (deuterated in this case), the chloride counterion remains in close proximity to the carbocation generated. Immediately following dissociation of DCl, the chloride ion is going to be much closer to C-2 than it is to C-4 , and therefore attack at C -2 is much faster. In fact, normal electrophilic addition of HX to conjugated alkenes in polar solvents can also proceed via similar ion pair mechanisms. This is reflected by the greater proportion of syn addition products to such substrates.
Exercise \(\PageIndex{1}\)
1) Why is the 1,4-addition product the thermodynamically more stable product?
2) Addition of 1 equivalent of bromine to 2,4-hexadiene at 0 degrees C gives 4,5-dibromo-2-hexene plus an isomer. What is the structure of that isomer?
3) The kinetically controlled product in the below reaction is:
4) For the reaction above, which product is the result of 1,4-addition?
5) What would be the major product of the addition of HBr to 2,3-dimethyl-1,3-cyclohexadiene under thermodynamic conditions?
6) Consider the reaction with 1,3-buta-diene reacting with HCl. Propose a mechanism for the reaction. Also, Predict why the 1,4 adduct is the major product in this reaction compared to the 1,2.
- Answer
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1) The 1,4- product is more thermodynamically stable because there are two alkyl groups on each side of the double bond and more substituted alkenes are more stable.
2) 2,5-Dibromo-3-hexene
3) 3-Chloro-1-butene
4) 1-Chloro-2-butene
5)
6)
Even though the cation would prefer to be in a secondary position in the transition state, the final product is less stable with a terminal alkene. Therefore the major product will be the 1,4 adduct.


7.6: Reading- Social Factors
People Influencing People
Social factors represent another important set of influences on consumer behavior. Specifically, these are the effects of people and groups influencing one another through culture and subculture, social class, reference groups, and family.
 Culture exerts a strong influence on a person’s needs and wants because it is through culture that we learn how to live, what to value, and how to conduct ourselves in society. The American culture, which is a subset of the Western (European) culture, will be the primary focus of this discussion, although other societies in other parts of the world have their own cultures with accompanying traditions and values.
Traditional American culture values include freedom, hard work, achievement, security, self-reliance, community involvement, and the like. Marketing strategies targeted to people with a common cultural heritage might demonstrate how a product or service reinforces these traditional values. There are three components of culture that members of that culture share: beliefs, values, and customs. As discussed in the prior section, a belief is a proposition that reflects a person’s particular knowledge or opinion of something. Values are general statements that guide behavior and influence beliefs. The function of a value system is to help people choose between alternatives in everyday life and prioritize choices that are most important to them personally.
Customs are traditional, culturally approved ways of behaving in specific situations. For example, in the United States, Thanksgiving is a holiday celebrated on the fourth Thursday in November with the custom of feasting with family and offering thanks for the things we appreciate in life. Taking your mother to dinner and giving her gifts for Mother’s Day is an American custom that Hallmark and other card companies support enthusiastically.
Understanding customs is hugely important for marketing to consumers, because many customs represent occasions for spending money, and culture dictates the appropriate things to buy in order to honor the custom. The power of culture is evident when you think about the tens of millions of Americans who buy Valentine’s Day flowers in February, chocolate Easter eggs in April, Independence Day fireworks in July, Halloween candy in October, and all kinds of food and gifts throughout the holiday season.
It is worth noting that for marketers anywhere in the world, it is essential to develop a strong understanding of the local culture and its accompanying beliefs, values, and customs. Culture is how people make sense of their society, its institutions, and social order. Culture frames how and what people communicate, how they express what is proper and improper, what is desirable and detestable. Without an understanding of culture, marketers are not really even speaking the right language to the consumers they want to target. Even if the words, grammar, and pronunciation are correct, the meaning will be off.
An expensive example of a massive cultural blunder was Wal-Mart’s short-lived foray into Germany. In 2006, the retailer pulled out of Germany after opening eighty-five stores in six years. The company expected success in Germany using the formula that works well in the U.S.: streamlined supply chain, low-priced products sold in big stores with wide selection and long operating hours. What Wal-Mart didn’t account for was the strong cultural preference in Germany for several things that directly oppose the Wal-Mart model. Germans prefer small and medium-sized retailers grounded in local communities. They have a cultural suspicion of low prices, which create concern about quality. German law includes significant restrictions on retail establishments’ operating hours and many labor protections, and these laws are viewed, in part, as important in protecting the German quality of life. Due in large part to these cultural disconnects, Wal-Mart was unable to sustain successful operations. [1]
Subculture
Subcultures are cohesive groups that exist within a larger culture. Subcultures develop around communities that share common values, beliefs, and experiences. They may be based on a variety of different unifying factors. For example, subcultures exist around the following:
- Geography: Southerners, Texans, Californians, New Englanders, midwesterners, etc.
- Ethnicity: Latinos, Asian Americans, African Americans, etc.
- Religion: Catholics, Jews, Mormons, Baptists, Muslims, etc.
- Nationality: Italians, Koreans, Hungarians, Japanese, Ethiopians, etc.
- Occupation: military, technology worker, state department, clergy, educator, etc.
Subcultures can represent huge opportunities for marketers to make a significant impact within a population that may feel underserved by companies operating in the mainstream market. Individuals with strong subcultural identity are likely to welcome organizations that seem to understand them, speak their subcultural language, and satisfy their subculture-specific needs.
In the United States, many organizations and marketing activities focus on major ethnicity-based subcultures such as Latinos, Asian Americans, and African Americans. Each subculture has distinct experiences living and working within the broader U.S. culture, and it has shared customs and values that shape their consumer needs and preferences. As each of these subcultures grows in size and buying power, they become a distinct market for companies to woo.
A noted example of effective marketing to a subculture is Ford Motor Company’s approach to serving the African American community. Ford invests in advertising campaigns that specifically target the black community and celebrate its diversity. Ford supports a number of scholarship and community-building programs at historically black colleges and universities (HBCUs). Through public relations activities, Ford maintains a presence at significant events, such as the Essence Festival and the BET Awards. [2]
The following video shows how a shopping mall managed to save itself by catering and marketing to the Latino subculture.
You can view the transcript for the video “Demise of the Mall and Reinvention” (opens in new window) .
Social Class
Some manifestation of social class is present in virtually every society. It’s determined by a combination of factors including family background, wealth, income, education, occupation, power, and prestige. Like culture, it affects consumer behavior by shaping individuals’ perceptions of their needs and wants. People in the same social class tend to have similar attitudes, live in similar neighborhoods, attend the same schools, have similar tastes in fashion, and shop at the same types of stores.
In some nations, the social class system is quite rigid, and people are strongly encouraged to stay within their own class for friendships, marriage, career, and other life decisions. In other countries, such as the United States, social class is more permeable, and people can move between classes more easily based on their circumstances, behaviors, and life choices. Social class mobility is an important value in mainstream American culture and is part of our collective belief system about what makes the nation great.
In the U.S., the most common social classification system is illustrated in the figure below.
Social Class in the United States
Upper Class makes up 1% of the population. Characteristics of the upper class include
- Heirs, celebrities, top corporate executives
- $500,000+ income
- Elite education is common
Upper Middle Class makes up 15% of the population. Characteristics of the upper middle class include
- Managers, professionals
- $100,000+ income
- Highly educated, college and graduate degrees are likely
Lower Middle Class makes up 32% of the population. Characteristics of the lower middle class include
- Skilled contractors, craftspeople, artisans, semi-professionals, autonomy in work environment is common
- $35,000 to $75,000 income
- Some college, training, secondary education is likely
Working class makes up 32% of the population. Characteristics of the working class include
- Clerical, blue- and pink-collar workers, job security is often a problem.
- $16,000 to $30,000 income
- High School Education
Lower Class makes up 20% of the population. Characteristics of the lower class include
- Poorly paid positions and/or reliance on government assistance
- Some high school education
Source: Thompson, W. & Hickey, J. (2005). Society in Focus. Boston, MA: Pearson, Allyn & Bacon.
For marketers, social class may be a useful factor to consider in segmentation and targeting. It provides helpful context about how consumers view themselves and their peer groups, their expectations, life experiences, income levels, and the kinds of challenges they face. For example, if a marketer wishes to target efforts toward the upper classes, they should realize that, first, this is a very small proportion of the population, and second, the market offering must be designed to meet their high expectations in terms of quality, service, and atmosphere. Having enough money is a persistent concern for people in the lower, working, and lower middle classes, so price sensitivity and value for the money are important for products targeting these groups.
Reference Groups
Consumer behavior can be influenced by the groups a person comes into contact with, through friendship, face-to-face interaction, and even indirect contact. Marketers often call these reference groups. A reference group may be either a formal or informal group. Examples include churches, clubs, schools, online social networks, play groups, professional groups, and even a group of friends and acquaintances. Individuals may be influenced by the groups of which they are members. They may also be influenced by aspirational groups –a reference group a person hopes to belong to one day, such as young boys hoping to grow up and become Major League Soccer (MLS) players.
Reference groups are characterized by having individuals who are opinion leaders for the group. Opinion leaders are people who influence others. They are not necessarily higher-income or better educated, but others may view them as having greater expertise, broader experience, or deeper knowledge of a topic. For example, a local high school teacher may be an opinion leader for parents in selecting colleges for their children. In a group of girlfriends, one or two may be the opinion leaders others look to for fashion guidance. These people set the trend and others conform to the expressed behavior. If a marketer can identify the opinion leaders for a group in the target market, then she can direct efforts towards attracting these people.
The reference group can influence an individual in several ways:
- Role expectations: Reference groups prescribe a role or way of behaving based on the situation and one’s position in that situation. For example, as a student, you are expected to behave in a certain basic way under certain conditions when interacting with a reference group at school.
- Conformity: Conformity the way we modify out behavior in order to fit in with group norms. Norms are “normal” behavioral expectations that are considered appropriate within the group. To illustrate, in a school lecture setting, you might conform to the group norm of raising your hand to make a comment or question, rather than shouting out to the teacher.
- Group communications through opinion leaders: As consumers, we are constantly seeking out the advice of knowledgeable friends or acquaintances who can provide information, give advice, or even make the decision for us. In some product categories, there are professional opinion leaders who are easy to identify, such as auto mechanics, beauticians, stock brokers, or physicians. In a school setting, an opinion leader might be a favorite teacher who does a good job explaining the material, a popular administrator who communicates well with students and parents, or a well-liked fellow student who is willing to assist when peers ask for help–or all of these individuals.
- Word-of-mouth influence: Consumers are influenced by the things they hear other people say. This is “word-of-mouth” communication. It happens every time you ask someone for a recommendation or an opinion about a product or service, and every time someone volunteers an opinion. Do you know a good dentist? Where should we go for lunch? Have you heard that new song from . . . ? Not surprisingly, research consistently shows that word-of-mouth information from people they know is more credible than advertising and marketing messages. Word-of-mouth influence in the school reference group example might include students discussing which Spanish instructor is better, or where to shop for a dress to wear to the homecoming dance.
Reference groups and opinion leaders are essential concepts in digital marketing, where consumers tap into a variety of social networks and online communities. Marketers need to understand which reference groups influence their target segments and who the opinion leaders within these groups are. Those leaders may be bloggers, individuals with many followers who post frequently on various social media, and even people who write lots of online reviews. Then marketing activity can focus on winning over the opinion leaders. If you manage to get the opinion leaders in your segment to “like” your product, “follow” your brand, tweet about your news and publish favorable reviews or comments on their blogs, your work with online reference groups is going well. (You’ll recall from the module on ethics that this was the strategy Microsoft adopted—and misgauged—when it attempted to influence opinion leaders with its gifts of free laptops loaded with its latest operating system.)
Family
One of the most important reference groups for an individual is the family. A consumer’s family has a major impact on attitude and behavior, and families themselves are critically important in society as consumer units. Many consumer decisions are made by family members on behalf of the family, so understanding the family consumer decision-making dynamics around your product is essential.
Depending on the product or service under consideration, different family members may be in the role of primary decision maker or influencer. In some cases, the husband is dominant, in others the wife or children, and still other cases, families make joint decisions. Traditionally the wife has made the primary decisions around store choice and brands for food and household items, although this has evolved somewhat as more women participate in the workforce. A joint decision is typical for purchases involving a larger sum of money, such as a refrigerator or a vehicle. Teenagers may exercise a lot of influence over their own clothing purchases. Children may heavily influence food and entertainment choices. Of course, decision dynamics within any individual family can vary, but marketers need to understand the general tendencies around family decision making for the product or service in question.
- https://journalofinternationalmanagement.wordpress.com/2011/05/16/walmarts-downfall-in-germany-a-case-study/ ↵
- www.foxbusiness.com/industries/2015/10/12/why-procter-gamble-mcdonalds-ford-are-chasing-black-consumer/, targetmarketnews.com/storyid06071201.htm ↵
Contributors and Attributions
- Revision and Adaptation. Authored by : Lumen Learning. License : CC BY: Attribution
- Chapter 4: Understanding Buyer Behavior, from Introducing Marketing. Authored by : John Burnett. Provided by : Global Text. Located at : http://solr.bccampus.ca:8001/bcc/file/ddbe3343-9796-4801-a0cb-7af7b02e3191/1/Core%20Concepts%20of%20Marketing.pdf . License : CC BY: Attribution
- A belated bouquet for YOU!. Authored by : Cheryl. Located at : https://www.flickr.com/photos/eraphernalia_vintage/4596842255/ . License : CC BY-SA: Attribution-ShareAlike
- Jeff Phillips SK8 Party. Authored by : Scott Lumley. Located at : https://www.flickr.com/photos/scottlumley/10692510614/ . License : CC BY: Attribution
- Shopping Family. Authored by : Tim Riley. Located at : https://www.flickr.com/photos/timriley/403254675/ . License : CC BY-NC-ND: Attribution-NonCommercial-NoDerivatives
- Alma de Mexico dancers at Latino Fest today in Lorain. Authored by : Rona Proudfoot. Located at : https://www.flickr.com/photos/ronnie44052/3938931572/ . License : CC BY-SA: Attribution-ShareAlike
- Demise of the Mall and Reinvention. Provided by : BBC. Located at : https://youtu.be/F_pHmmVov34 . License : CC BY-NC-ND: Attribution-NonCommercial-NoDerivatives


16.7: Selected Moons of the Planets (Appendix G)
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Note: As this book goes to press, nearly two hundred moons are now known in the solar system and more are being discovered on a regular basis. Of the major planets, only Mercury and Venus do not have moons. In addition to moons of the planets, there are many moons of asteroids. In this appendix, we list only the largest and most interesting objects that orbit each planet (including dwarf planets). The number given for each planet is discoveries through 2015. For further information see https://solarsystem.nasa.gov/planets/solarsystem/moons and https://en.Wikipedia.org/wiki/List_of_natural_satellites .
| Planet (moons) | Satellite Name | Discovery | Semimajor Axis (km × 1000) | Period (d) | Diameter (km) | Mass (10 20 kg) | Density (g/cm 3 ) |
|---|---|---|---|---|---|---|---|
| Earth (1) | Moon | — | 384 | 27.32 | 3476 | 735 | 3.3 |
| Mars (2) | Phobos | Hall (1877) | 9.4 | 0.32 | 23 | 1 × 10 −4 | 2.0 |
| Deimos | Hall (1877) | 23.5 | 1.26 | 13 | 2 × 10 −5 | 1.7 | |
| Jupiter (79) | Amalthea | Barnard (1892) | 181 | 0.50 | 200 | — | — |
| Thebe | Voyager (1979) | 222 | 0.67 | 90 | — | — | |
| Io | Galileo (1610) | 422 | 1.77 | 3630 | 894 | 3.6 | |
| Europa | Galileo (1610) | 671 | 3.55 | 3138 | 480 | 3.0 | |
| Ganymede | Galileo (1610) | 1070 | 7.16 | 5262 | 1482 | 1.9 | |
| Callisto | Galileo (1610) | 1883 | 16.69 | 4800 | 1077 | 1.9 | |
| Himalia | Perrine (1904) | 11,460 | 251 | 170 | — | — | |
| Saturn (82) | Pan | Voyager (1985) | 133.6 | 0.58 | 20 | 3 × 10 −5 | — |
| Atlas | Voyager (1980) | 137.7 | 0.60 | 40 | — | — | |
| Prometheus | Voyager (1980) | 139.4 | 0.61 | 80 | — | — | |
| Pandora | Voyager (1980) | 141.7 | 0.63 | 100 | — | — | |
| Janus | Dollfus (1966) | 151.4 | 0.69 | 190 | — | — | |
| Epimetheus | Fountain, Larson (1980) | 151.4 | 0.69 | 120 | — | — | |
| Mimas | Herschel (1789) | 186 | 0.94 | 394 | 0.4 | 1.2 | |
| Enceladus | Herschel (1789) | 238 | 1.37 | 502 | 0.8 | 1.2 | |
| Tethys | Cassini (1684) | 295 | 1.89 | 1048 | 7.5 | 1.3 | |
| Dione | Cassini (1684) | 377 | 2.74 | 1120 | 11 | 1.3 | |
| Rhea | Cassini (1672) | 527 | 4.52 | 1530 | 25 | 1.3 | |
| Titan | Huygens (1655) | 1222 | 15.95 | 5150 | 1346 | 1.9 | |
| Hyperion | Bond, Lassell (1848) | 1481 | 21.3 | 270 | — | — | |
| Iapetus | Cassini (1671) | 3561 | 79.3 | 1435 | 19 | 1.2 | |
| Phoebe | Pickering (1898) | 12,950 | 550 (R) 1 | 220 | — | — | |
| Uranus (27) | Puck | Voyager (1985) | 86.0 | 0.76 | 170 | — | — |
| Miranda | Kuiper (1948) | 130 | 1.41 | 485 | 0.8 | 1.3 | |
| Ariel | Lassell (1851) | 191 | 2.52 | 1160 | 13 | 1.6 | |
| Umbriel | Lassell (1851) | 266 | 4.14 | 1190 | 13 | 1.4 | |
| Titania | Herschel (1787) | 436 | 8.71 | 1610 | 35 | 1.6 | |
| Oberon | Herschel (1787) | 583 | 13.5 | 1550 | 29 | 1.5 | |
| Neptune (14) | Despina | Voyager (1989) | 53 | 0.33 | 150 | — | — |
| Galatea | Voyager (1989) | 62 | 0.40 | 150 | — | — | |
| Larissa | Voyager (1989) | 118 | 1.12 | 400 | — | — | |
| Triton | Lassell (1846) | 355 | 5.88 (R) 2 | 2720 | 220 | 2.1 | |
| Nereid | Kuiper (1949) | 5511 | 360 | 340 | — | — | |
| Pluto (5) | Charon | Christy (1978) | 19.7 | 6.39 | 1200 | — | 1.7 |
| Styx | Showalter et al (2012) | 42 | 20 | 20 | — | — | |
| Nix | Weaver et al (2005) | 48 | 24 | 46 | — | 2.1 | |
| Kerberos | Showalter et al (2011) | 58 | 24 | 28 | — | 1.4 | |
| Hydra | Weaver et al (2005) | 65 | 38 | 61 | — | 0.8 | |
| Eris (1) | Dysnomea | Brown et al (2005) | 38 | 16 | 684 | — | — |
| Makemake (1) | (MK2) | Parker et al (2016) | — | — | 160 | — | — |
| Haumea (2) | Hi’iaka | Brown et al (2005) | 50 | 49 | 400 | — | — |
| Namaka | Brown et al (2005) | 39 | 35 | 200 | — | — |
Footnotes
1 R stands for retrograde rotation (backward from the direction that most objects in the solar system revolve and rotate).
2 R stands for retrograde rotation (backward from the direction that most objects in the solar system revolve and rotate).