JEE Main 2026 Physics question
The time taken by a block of mass m to slide down from the highest point to the lowest point on a rough inclined plane is 50% more compared to the time taken by the same block on identical inclined smooth plane. Both inclined planes are at 45° with the horizontal. The coefficient of kinetic friction between the rough inclined surface and block is .
Answer: (C)
Solution
/ = √/ = 1.5. With = g sin45° and = g sin45°(1−μ): 1/(1−μ) = 2.25, giving μ = 5/9.