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class=sites-canvas-main id=sites-canvas-main><div id=sites-canvas-main-content><table class="sites-layout-name-one-column sites-layout-hbox"cellspacing=0 xmlns=http://www.w3.org/1999/xhtml><tbody><tr><td class="sites-layout-tile sites-tile-name-content-1"><div dir=ltr><hr><h2><a name=TOC-Introduction> </a> Introduction</h2><div class=sites-embed-align-right-wrapping-on><div class="sites-embed-border-off sites-embed"style=width:250px;><div class="sites-embed-content sites-embed-type-toc"><div class="goog-toc sites-embed-toc-maxdepth-6"><p>Contents<ol class=goog-toc><li class=goog-toc><a href=#TOC-Introduction> <strong> 1 </strong> Introduction </a><li class=goog-toc><a href=#TOC-Resources-Links> <strong> 2 </strong> Resources/Links </a><li class=goog-toc><a href=#TOC-Learning-Objectives:> <strong> 3 </strong> Learning Objectives: </a><li class=goog-toc><a href=#TOC-Building-and-Racing:> <strong> 4 </strong> Building and Racing: </a><li class=goog-toc><a href=#TOC-Safety:> <strong> 5 </strong> Safety: </a><li class=goog-toc><a href=#TOC-Assembly-and-Materials:> <strong> 6 </strong> Assembly and Materials: </a><li class=goog-toc><a href=#TOC-Frame-Chassis-> <strong> 7 </strong> Frame (Chassis) </a><li class=goog-toc><a href=#TOC-Wheels-and-Axels> <strong> 8 </strong> Wheels and Axels </a><li class=goog-toc><a href=#TOC-Pulling-String> <strong> 9 </strong> Pulling String </a><li class=goog-toc><a href=#TOC-Lever-Arm> <strong> 10 </strong> Lever Arm </a></ol></div></div></div></div><div><div>A mouse-trap car is a vehicle that is powered by the energy that can be stored in a wound up mouse-trap spring. The most basic design is as follows: a string is attached to a mouse-trap’s lever arm and then the string is wound around a drive axle causing the mouse-trap’s spring to be under tension. Once the mouse-trap’s arm is released, the tension of the mouse-trap’s arm pulls the string of the drive axle causing the drive axle and the wheels to rotate, propelling the vehicle.</div></div><h2><a name=TOC-Resources-Links> </a> Resources/Links</h2><div><div class=sites-embed-align-left-wrapping-off><div class="sites-embed-border-on sites-embed sites-embed-full-width"style=width:100%;><div class="sites-embed-content sites-embed-type-ggs-gadget"><div><iframe title="Slim RSS Reader"allowtransparency class=igm frameborder=0 height=200 id=1060564173 name=1060564173 scrolling=auto src=javascript:void(0); width=100%></iframe><script>JOT_postEvent('registerForRpc', this, ['5002253298398047963', 1060564173, '//pfhd07ql0n7bakmio5rv1droe2ihhvd0-a-sites-opensocial.googleusercontent.com/gadgets/ifr?url\x3dhttp://1o4.jp/google/module/slim-reader.xml\x26container\x3denterprise\x26view\x3ddefault\x26lang\x3den\x26country\x3dALL\x26sanitize\x3d0\x26v\x3d9f4bac8a67c30c38\x26up_contentsnum\x3d9\x26up_mfeed\x3dhttps://www.diigo.com/list/Kurtusu/stem-mouse-trap-car/rss.xml\x26up_mtitle\x3dLinks\x26up_titlelink\x3dhttp://googleblog.blogspot.com/\x26libs\x3dcore:dynamic-height:setprefs\x26mid\x3d88\x26parent\x3dhttps://sites.google.com/a/littleblue.usu.edu/stem/topics/mouse-trap-car#st\x3de%3DAIHE3cAHaeoF9yXhkBK6escZhra9pzlty8hTrO3oLzUKDrmfyES2Hjh5lvYE4bksUoqo09Ehuts7sg7tV8d1%252FeHzjr3pAyJH0yuAPYDw36zLUsBLYUB82hhTiLKbOcPzFme0fqN1mGjS%26c%3Denterprise\x26rpctoken\x3d5002253298398047963'])</script></div></div></div></div></div><div><br></div><h2><a name=TOC-Learning-Objectives:> </a> Learning Objectives:</h2><ul><li>To develop an understanding for the holistic design process.<li>Develop a solution to solve a real life problem.<li>Sketching ideas.<li>Develop researching skills using the internet.<li>Develop an understanding of the properties of basic engineering forces (Energy, Forces, Motion).</ul><div><h2><a name=TOC-Building-and-Racing:> </a> Building and Racing:</h2> Only one standard (5 x 10 cm) mousetrap may be used. To ensure that everyone has the same power source, the mouse trap must be the one given to your child by his/her teacher. The trap must remain intact; the spring cannot be modiﬁed or moved from the wood base of the mouse trap. Screws and nails, zip ties for example, can be used to attach the mousetrap to the car chassis, but wood cannot be cut or removed from the base. No launching ramps are allowed; all parts of the vehicle must move forward as a whole. The only energy source allowed at the start of the race is that which is stored in the mousetrap spring. You may not hold the vehicle during release or push the vehicle. <br><h2><a name=TOC-Safety:> </a> Safety: <img style="display:inline;margin:5px 10px;float:right"border=0 height=266 src=http://justindenomme101.wikispaces.com/file/view/justin-mtc.png/116372027/800x532/justin-mtc.png width=400></h2><span style=font-size:1em;line-height:1.5> It is highly recommended that you “disarm” your mouse trap during  </span><span style=font-size:1em;line-height:1.5> construction. This can be accomplished by sliding the long spring arm off of the  </span><span style=font-size:1em;line-height:1.5> hammer. St no time during construction does your trap need to be “set”. </span></div><div><br><br><h2><a name=TOC-Assembly-and-Materials:> </a> Assembly and Materials:</h2> Before beginning the Mouse Trap Car Race Project, it is strongly recommended that parents and students read through this guide and refer to the Mouse Trap Car Rase links on the EBLS website for additional speciﬁcations and construction tips. <br><br> Experimentation is essential in order to achieve maximum performance.  Experiment often and early, don’t worry about making mistakes! Making a mistake is a learning experience. Keep in mind you will not know many of the problems until you encounter them as you build your car. Engineering is a process by which ideas are tested and re-tested in an effort to produce the best working product. A good engineer knows one way to get something to work and 99 ways it won’t work. <br><br> Almost any materials can be used in the construction of a good mouse-trap car. It is up to the designer to determine the appropriate application of such materials. Sizes, lengths, diameters, widths, and kinds of materials are more-or-less left up to the designer. The human imagination is a wonderful gift, and our own ingenuity allows us to take ordinary objects with functions different from what were intended and turn them into components of a working machine. <br><br><span style=font-size:1em;line-height:1.5> The following illustration will identify some the components that you need to  </span> consider when engineering your car.  <div style="display:inline;margin:5px 10px;float:right"><a href=https://sites.google.com/a/littleblue.usu.edu/stem/topics/mouse-trap-car/Screen%20Shot%202013-03-12%20at%204.56.56%20PM.png?attredirects=0 imageanchor=1> <img border=0 height=251 src=https://sites.google.com/a/littleblue.usu.edu/stem/_/rsrc/1363129067570/topics/mouse-trap-car/Screen%20Shot%202013-03-12%20at%204.56.56%20PM.png?height=251&width=400 width=400> </a></div><br><br><h2><a name=TOC-Frame-Chassis-> </a> <span style=font-size:1em;line-height:1.5> Frame (Chassis) </span></h2><span style=font-size:1em;line-height:1.5> The chassis is a mechanical component that must provide structural support for  </span> the motor, wheels, axles, etc. It is important that your mouse-trap car’s chassis is designed to handle the operations of your vehicle. There are some important tradeoffs that need to be considered. A chassis that is too light may be too delicate to handle the force of a wound up mouse-trap spring. Also, a chassis that is too light will have less weight pushing down on the wheels, causing less tire traction. A chassis that is too heavy will require more energy at the start than a lighter frame. The chassis needs to be strong and stiff. Strong means that it will not beak under a load. Stiff means it will not bend or has little ﬂex. The ﬁrst step to a strong, stiff, and light chassis is choosing the right materials. Balsa wood, pine, or bass wood are excellent choices although balsa wood is somewhat brittle and hard to drill holes into without ripping. Other materials can also be used for making a light weight strong and stiff frame. These include Styrofoam, corrugated cardboard, plastics, aluminum. <br><h2><a name=TOC-Wheels-and-Axels> </a> Wheels and Axels</h2><span style=font-size:1em;line-height:1.5> The number of wheels your vehicle has does not necessarily have an effect on the  </span> overall performance of your car. The advantage of using fewer wheels however, is better wheel alignment. With three-wheeled cars, it will be easier to adjust the steering of the vehicle because there are fewer wheels to be aligned. The advantage of using four wheels is the car stability.  <br><br> You should consider the diameter of the wheels in the construction of your vehicle. The number of turns a wheel makes has an effect on the energy consumed by a wheel. Large diameter wheels will make fewer turns over the same distance compared to smaller diameter wheels, thus reducing the total amount of energy needed to overcome friction and allowing a vehicle to travel a longer distance. On mouse-trap cars, smooth tires will allow a vehicle to travel a longer distance. (See tips for making BIG wheels)  <br><br> Some of the best wheels are found in your home: old compact discs, Styrofoam®, can lids and tops, records, mat board, or other light-weight materials.  <br><br> Use a large wheel with a small axle (i.e., a large wheel-to-axle ratio). A large wheel with a small axle will cover more distance per each turn of the axle when compared to a smaller wheel with the same axle. Axels can be successfully made from just about any “rod” type material. Straws, skewers, pencils (round not hex-shaped), dowels, hangers. The wheels must be securely attached to the axels. With distance vehicles, you want a small force over a long distance; therefore, use a large wheel with a small axle. <br><br> The one secret that I can share with you that will most improve your car’s performance is the following: REMOVE MASS FROM YOUR WHEELS. By cutting out sections of the wheels, your wheels will require less force and energy to turn and accelerate. You can also improve performance by removing mass from the frame.  <br><h2><a name=TOC-Pulling-String> </a> Pulling String</h2><span style=font-size:1em;line-height:1.5> String is often used to transfer a force from one point to another. Choosing the  </span> proper string is critical. If you use a string that cannot handle the pulling force, it will snap as you release the mouse trap. If you use a string that is too thick, it will not wind around the drive axle smoothly, causing the pulling force to be inconsistent. DO NOT USE THREAD. The string must not be tied to the axle. If the string is tied to the axle, it will begin to rewind itself and will cause your car to come to a sudden stop. In order to achieve maximum performance from your mouse-trap car, it is important that the pulling string does not slip off the drive axle prematurely. A release hook can be constructed to allow the string to remain connected to the axle during the pulling phase and then release once the pulling has stopped.  <br><h2><a name=TOC-Lever-Arm> </a> Lever Arm</h2><span style=font-size:1em;line-height:1.5> The distance from the turning axis to the point of contact is called the lever arm.  </span> By adjusting the length of the mouse trap’s lever arm, you can vary the force that is applied to the wheels of your car. Long lever arms decrease the pulling force while short arms increase the pulling force. The longer the length of the lever arm that you use, the more string you can wind around the drive axle. Therefore,  <span style=font-size:1em;line-height:1.5> a greater overall travel distance can occur as the string is pulled off the drive  </span><span style=font-size:1em;line-height:1.5> axle. Lever arms should not extend past the axle when in the lowered position.  </span><span style=font-size:1em;line-height:1.5> For correct lever arm length make sure the lever reaches the axle. If the lever  </span><span style=font-size:1em;line-height:1.5> end is L-shaped then it will center the string on the axle. When cutting the mouse  </span><span style=font-size:1em;line-height:1.5> trap hammer to add length to the lever arm be sure you remove the side (arm of  </span><span style=font-size:1em;line-height:1.5> the hammer) that does not attach to the long arm of the spring.  </span></div><div><br> Eliminating all forms of friction is the key to success no matter what type of vehicle you are building. Minimizing surface friction on a mouse-trap car allows its wheels to spin with less resistance, resulting in a car that travels faster, farther and wastes less energy. The most common area where surface friction will occur is between the axle and the chassis.  <br><br> Look your car over with a scrutinizing eye in order to reduce the total amount of friction acting on your vehicle. </div><div><br></div></div></table></div></div><div id=sites-canvas-bottom-panel><div id=COMP_page-subpages xmlns=http://www.w3.org/1999/xhtml></div><div id=sites-attachments-container></div><a name=page-comments xmlns=http://www.w3.org/1999/xhtml> </a><div id=COMP_page-comments xmlns=http://www.w3.org/1999/xhtml><div class=sites-comment-docos-wrapper><div class=sites-comment-docos><div class=sites-comment-docos-background></div><div class=sites-comment-docos-header><div class=sites-comment-docos-header-title>Comments</div></div><div class=sites-comment-docos-pane id=sites-comment-docos-pane></div></div></div></div></div></div></table></div></div><div id=sites-chrome-footer-wrapper><div id=sites-chrome-footer-wrapper-inside><div id=sites-chrome-footer></div></div></div></div></div><div id=sites-chrome-adminfooter-container><div class=sites-adminfooter role=navigation xmlns=http://www.w3.org/1999/xhtml><p><a class=sites-system-link href=https://accounts.google.com/ServiceLogin?continue=https://sites.google.com/a/littleblue.usu.edu/stem/topics/mouse-trap-car&service=jotspot> Sign in </a> <span aria-hidden=true> | </span> <a class=sites-system-link href=/a/littleblue.usu.edu/stem/system/app/pages/recentChanges> Recent Site Activity </a> <span aria-hidden=true> | </span> <a class=sites-system-link href=https://sites.google.com/a/littleblue.usu.edu/stem/system/app/pages/reportAbuse target=_blank> Report Abuse </a> <span aria-hidden=true> | </span> <a class=sites-system-link href=javascript:; onclick=window.open(webspace.printUrl)> Print Page </a> <span aria-hidden=true> | </span> <span class=sites-system-link> Powered By </span> <b class=powered-by> <a href=http://sites.google.com/site> Google Sites </a> </b></div></div></div></div><script xmlns=http://www.w3.org/1999/xhtml>window.jstiming.load.tick('sjl');</script><script src=https://ssl.gstatic.com/sites/p/d955fc/system/js/jot_min_view__en.js xmlns=http://www.w3.org/1999/xhtml></script><script xmlns=http://www.w3.org/1999/xhtml>window.jstiming.load.tick('jl');</script><script xmlns=http://www.w3.org/1999/xhtml>sites.Searchbox.initialize(
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