a block of mass 15 kg is placed on a long trolley.the co effucient of static friction btw the block and the trolley is 0.18.the trolley accelerates from rest with o.5ms2 the friction btw the block and trolley is
Answers
Mass of the block, m = 15 kg
Coefficient of static friction, = 0.18
Acceleration of the trolley, a = 0.5 m/s
As per Newton's second law of motion, the force (F) on the block caused by the motion of the trolley is given by the relation:
F = ma = 15 x 0.5 = 7.5 N
This force is acted in the direction of motion of the trolley.
Force of static friction between the block and the trolley:
f = mg
= 0.18×15× 10 = 27 N
The force of static friction between the block and the trolley is greater than the applied external force. Hence, for an observer on the ground, the block will appear to be at moving with constant acceleration.
When the trolley moves with uniform velocity there will be no applied external force. Only the force of friction will act on the block in this situation.