When an object falls, its GPE is converted into KE, meaning the further it falls, the faster it will go (because before the object fell, it must have had a lot of energy stored in it, more so than an object at a lower height).
Although some of the GPE will be dissipated as heat because of air resistance, in the exam, they'll likely to ignore this factor, and so you should say that:
Kinetic energy gained = Potential Energy (i.e. GPE) lost
For example, an object with GPE 300J will fall with 300J of KE
Hard question example:
A 600kg (6000N) Mini is travelling at 50 m/s. What is the maximum height it could climb if all its KE is transferred to GPE?
KE =1/2 x 600 x (50x50) = 750,000 J = GPE gained
GPE = 750,000 J 750,000 = 6000 x Height Height = 750,000/6000 = 125 m
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