Q 11-05-035NEETJEE MainEasy
A $2$ kg block moving at $6$ m/s on a rough horizontal floor comes to rest after sliding $4.5$ m. The coefficient of kinetic friction is ($g = 10\ \text{m/s}^2$)
Answer: (B) $0.4$
Concept. Friction removes all the KE: $\mu mgd = \dfrac12mv^2$.
Step 1. Solve. $\mu = \dfrac{36}{90} = 0.4$.
Answer. $0.4$ (Option B).
Solution by Sreeraj P, M.Sc Physics