JEE Main 2026 — Work Power Energy Question with Solution

Using the work-energy theorem, the total work done on the ball is equal to its change in kinetic energy.

Since the ball starts from rest and finally comes to rest, the change in kinetic energy is zero.

$W_{\text{gravity}}+W_{\text{sand}}=\Delta K=0$

The work done by gravity is over the total distance $h+d$, and the work done by the resistive force of the sand $F$ is over the distance $d$.

$mg(h+d)-Fd=0$

$F=\frac{mg(h+d)}{d}$

Given $m=2$ kg, $g=10$ m/s${}^2$, $h=10$ m, and $d=10$ cm $=0.1$ m:

$F=\frac{2\times 10\times (10+0.1)}{0.1}$

$F=\frac{20\times 10.1}{0.1}$

$F=20\times 101=2020$ N

Answer: $2020$