Q 11-05-109JEE MainJEE Main 2023 (6 Apr, Shift 1)Medium
A particle of mass $10\ \text{g}$ moves in a straight line with retardation $2x$, where $x$ is the displacement in SI units. Its loss of kinetic energy for above displacement is $10^{-n}x^2$ J. The value of $n$ will be ______.
Numerical value type. Enter your answer.
Answer: 2
Retarding force $F=m\times2x=0.02x\ \text{N}$.
$$\Delta K=\int_0^x0.02x\,dx=0.01x^2=10^{-2}x^2\ \text{J}$$
So $n=2$.
Solution by Sreeraj P, M.Sc Physics