If an Object is Falling Without Friction, What Happens to the Energy?

Most recent answer: 09/29/2015

Q:
If an object is falling without friction, what happens to the energy? Does it increase, decrease or remain constant?
- Taylar (age 18)
Windsor
A:

Hello Taylar

If there is no friction then energy is conserved.  There are two parts in this case, potential energy and kinetic energy.   The object starts out with no kinetic energy and potential energy of  PE = mgh where m is the mass, g is acceleration due to gravity and h is its initial height above the ground. The kinetic energy is zero.  As the object falls it loses potential energy and gains kinetic energy KE = mv2/2.   The sum PE and KE remain constant.  When the object reaches the ground its final KE will be equal to its original PE.

LeeH

 


(published on 09/29/2015)