Activity 1.1.1 Simple Machine Investigation – VEX Introduction Greek mathematician, physicist, astronomer, and engineer Archimedes boasted, “Give me a place to stand, and with a lever I will move the whole world.” Archimedes never moved the world, but he did change the world through the development of simple machine mechanisms. In this activity you will explore the function and characteristics of the lever, wheel and axle, and pulley systems. ou will see firsthand how simple machines manipulate energy to create a desired output.
Equipment • • • • • •
!"# $#% kit components &ulers and'or tape measures (tring ) *asonry line $ernier Interface $ernier +ual&ange -orce (ensor $ernier ogger!ro software
Procedure -or this activity your team of four will construct simple machines using $#% components. After you have constructed the simple machines, you will gather data to calculate mechanical advantage. It is important to be as accurate as possible in your measurements and documentation. /erms to know to complete this activity0 /he Eort !"E# is the force that you apply to the system. /he $esistance !"$# is the force or load that you are manipulating.
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Part 1 – %ever& 'heel and A(le& and Pulley "irst )lass %ever 4. 7reate a scaled annotated drawing of the first class lever.
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=. ist and describe two examples of a first class lever. /wo examples of a first class lever include seesaw and a weighing scale.
Second )lass %ever 4 7reate a scaled annotated drawing of the second class lever.
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44. ist and describe two examples of a second class lever. /wo examples of a second class lever include a stapler and wheel barrow.
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*hird )lass %ever 4 7reate a scaled annotated drawing of the third class lever.
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4=.ist and describe two examples of a third class lever. /wo examples of third class levers include tennis rackets and tweeers. 49.Is it possible for a first or second class lever to have a mechanical advantage less than one, or for a third class lever to have a mechanical advantage greater than oneB Custify your answer.
Do, a second class lever always has a mechanical advantage over 4.
Do, a third class lever always has a mechanical advantage less than 4.
1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age =
4>.6hen you were solving for mechanical advantage, what units did the final answer reEuireB #xplain why.
'heel and A(le 4 6hat is the diameter of the +heelB ; cm 4?.6hat is the diameter of the a(leB .: cm 23.Attach the resistance weight to the string attached to the axle. Fse your fingers to turn the wheel. ased on where the applied effort and resistance are located, identify the distance traveled by both forces during one full rotation. ,E - ,$ - ./
24.&emove the resistance weight from the axle string and attach the weight to the wheel. Fse your fingers to turn the axle. ased on where the applied effort and resistance are located, identify the distance traveled by both forces during one full rotation. ,E -0 ,$ - ./
22.6rap the resistance weight around the axle using string. Fse the force sensor attached to the string wrapped around the wheel to create eEuilibrium. ased on where the applied effort and resistance are located, identify the force reEuired to hold the system in eEuilibrium. "E -2 "$ - 1
4. 6rap the weight around the wheel using string. Fse the force sensor attached to string on the axle to create eEuilibrium. ased on where the applied effort and resistance are located, identify the force reEuired to hold the system in eEuilibrium. "E -/ "$ - 1./
2<. -or the same resistance, is the effort force larger when the eort is applied to the +heel or when it is applied to the a(leB #xplain why. 1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age 9
/he axle, because it has less distance effort, but conseEuently it reEuires more force resistance.
2;.7reate a scaled annotated drawing of the wheel and axle system. 2:.ist and describe two examples of a wheel and axle. 7ar and ferris wheel 2=.If you know the dimensions of a wheel and axle system used for an automobile, how can you determine the distance covered for each axle revolutionB #xplain any additional information and necessary formulas. es, you can determine the distance the distance covered by each axle revolution. 29.6hy is the steering wheel on a school bus so largeB ecause it has a bigger load, therefore it needs more effort.
"i(ed Pulley
1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age >
4 7reate a scaled annotated drawing of the fixed pulley system.
Mova3le Pulley 1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age ?
4 7reate a scaled annotated drawing of the pulley system.
4loc5 and *ac5le 4 7reate a scaled annotated drawing of the pulley system.
1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age 43
+escribe two examples of a pulley system. 6ell and elevator
1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age 44
Part – Inclined Plane and Scre+ Inclined Plane 4 7reate a scaled annotated drawing of the inclined plane system.
2.
7alculate the ideal mechanical advantage of the inclined plane system.
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7alculate the actual mechanical advantage of the inclined plane system.
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2. ist and describe two examples of an inclined plane. Handicap & and (lide
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+escribe two examples of a screw. A lid of 5ar /he bottom part of a lightbulb
<. 6hy do you think overcoming a resistance force using a screw is so easyB 1 2342 !ro5ect ead /he 6ay, Inc. !rinciples "f #ngineering Activity 4.4.4 (imple *achine Investigation $#% ) !age 4<
/he ridges on the screw help it to easily create grooves into the substance.
;. /he screw is a combination of two simple machines. Identify and defend what two simple machines you believe are combined to create a screw. Inclined plane0 *akes the ridges on cylinder to create the screw 6edge0 the part that goes inside is called the wedge
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