Q 11-05-100JEE MainJEE Main 2023 (13 Apr, Shift 2)Easy
A car accelerates from rest to $u\ \text{m s}^{-1}$. The energy spent in this process is $E$ J. The energy required to accelerate the car from $u\ \text{m s}^{-1}$ to $2u\ \text{m s}^{-1}$ is $nE$ J. The value of $n$ is ______.
Numerical value type. Enter your answer.
Answer: 3
$E=\tfrac12mu^2$. From $u$ to $2u$: $\tfrac12m(4u^2-u^2)=3E$. So $n=3$.
Solution by Sreeraj P, M.Sc Physics