Q5.35 A block of mass 15 kg is placed on a long trolley. The coefficient of static friction between the block and the trolley is 0.18. The trolley accelerates from rest with 0.5 m s-2 for 20 s and then moves with uniform velocity. Discuss the motion of the block as viewed by (a) a stationary observer on the ground.
(a) Using Newton's second law of motion we can write :
or Its direction is in the direction of motion of trolley.
The frictional force is
or
Since the frictional force is greater than the applied force so the block will appear to be at rest when seen by any stationary person.