A wooden block is gently pressed against a rough vertical wall
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A 3.0kg wooden block is gently pressed against a rough vertical wall. The horizontal force applied to the block is increased very slowly from zero until the block just starts to slide. The coefficients of friction are μs=0.40 and μk=0.30. After the instant the block starts sliding, the horizontal force is kept constant at this critical value. Take g=9.8ms−2.
(i) Determine the value of the horizontal force at the moment the block begins to move.
(ii) Calculate the vertical acceleration of the block immediately after it starts sliding.
(iii) Find the speed of the block after it has descended 0.50m from the point where motion began.