Q 11-05-059JEE MainJEE Main 2025 (22 Jan, Shift 2)Easy
A force $\vec F = 2\hat i + b\hat j + \hat k$ is applied on a particle and it undergoes a displacement $\hat i - 2\hat j - \hat k$. What will be the value of $b$, if work done on the particle is zero?
Answer: (B) $\dfrac{1}{2}$
$$W = \vec F\cdot\vec s = (2)(1) + (b)(-2) + (1)(-1) = 1 - 2b$$
$W = 0 \Rightarrow b = \dfrac{1}{2}$
Solution by Sreeraj P, M.Sc Physics