Does an Object Lose Potential Energy as It Gains Kinetic Energy?

[anthroxy]

Hi i was just wondering if a object loses potential energy at the same rate as it gains kinetic engergy. Does the object have to be in free fall and are all the resulting forces equal to zero at this point?

 

[Doc Al]

Hi i was just wondering if a object loses potential energy at the same rate as it gains kinetic engergy. Does the object have to be in free fall and are all the resulting forces equal to zero at this point?

No, the object need not be in free fall--a box sliding down a frictionless ramp will also gain KE at the same rate as it loses gravitational PE. All that matters is that there's no dissipative forces like friction or air resistance.

And no, the resultant force is not zero! An object in free fall has a net downward force --its weight.

 

[anthroxy]

So if we neglect air resistance we can more or less say that we lose PE at the same rate as we gain KE, thanks a lot!