A block of mass m is gently placed over a massive plank moving horizontally over a smooth surface with velocity 10 m s - 1 . The coefficient of friction between the block and the plank is 0 . 2 . The distance travelled by the block till it slides on the plank is g = 10 m s - 2

Step-by-step solution

Initially the block is not moving with respect to ground while plank is moving, it means, relative motion is there between the plank and block due to which friction (kinetic) starts acting. Initial velocity of block is zero and final velocity is 10  m / s and let s is the distance travelled by the block over the ground, then:- m 10 2 2 - m 0 2 2 = 0 .2 × m × 10 × s ⇒ 50 = 2 s ⇒ s = 25   m