A body is falling from a height h. After it has fallen a height h/2, it will possess
(a) only potential energy
(b) only kinetic energy
(c) half potential and half kinetic energy
(d) more kinetic and less potential energy
Answer: [C]
Solution.
When a body is dropped from a height, it gets acceleration due to gravity.
Acceleration increases its speed; hence its kinetic energy keeps on increasing.
The ball is dropped from height H, and we are analyzing the ball at height H/2.
The total energy of the ball will not change in free fall under gravity.
As the height becomes half of the initial height, the potential energy will become half.
This decrease in potential energy, will come in the form of kinetic energy because total energy is conserved.
Therefore, kinetic energy of the ball will be half of initial potential energy.
Hence, the correct answer to this question is option C.