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Studying for test please confirm this

  • Thread starter onrytxn
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  • #1
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For a given system in which energy is conserved, how do you use the concept of conservation of energy to find the velocity of a falling object, given its mass, original height of elevation, and the distance it has fallen?

Find Total Energy; @ high point PEmax=mgh; @btm point KEmax= ½ mv^2; equate PE=KE; @ a position in between Total Energy =PE+KE @ that point.

Does this sound right?
 

Answers and Replies

  • #2
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Yep, it does sound right to me. Just equate the change in potential energy (given that initial speed is zero) with the change in kinetic energy to get the speed. This equation then holds for every point between the two limit positions. Another nice result is that the speed is independent of the object's mass.
 
  • #3
For any position in between PE=KE is wrong. But total energy=PE + KE is correct for any point in the path.

As the question suggests all it's looking for is showing an understanding to TOTAL ENERGY=POTENTIAL ENERGY+KINETIC ENERGY at any point.

Best of luck for your exam :)
 

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