A cubic block of mass m is sliding down on an inclined plane at 60 ° with an acceleration of g/2 , the value of coefficient of kinetic friction is

Physics · Friction

JEE Main 2025 — 7 April, Morning Shift — Question 52

A cubic block of mass $m$ is sliding down on an inclined plane at $60^{\circ}$ with an acceleration of

$\frac{g}{2}$ , the value of coefficient of kinetic friction is

$a=\frac{m g \sin \theta-\mu m g \cos \theta}{m}=\frac{g \sqrt{3}}{2}-\frac{\mu g}{2}$

\begin{aligned} & \Rightarrow \quad \frac{g}{2}=\frac{g}{2}(\sqrt{3}-\mu) \Rightarrow \sqrt{3}-\mu=1 \\ & \Rightarrow \mu=(\sqrt{3}-1) \approx 1.73-1=0.73 \end{aligned}

Answer key and solution verified before publishing.

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.