Q.1)  A uniform rod AB of mass m and length l is at rest on a smooth horizontal surface. An impulse p is applied to the end B. Find the time taken by rod to turn through a right angle?

Q.2)   Two blocks of masses 10kg and 4kg connected by a spring of negligible mass and placed on a frictionless horizontal surface. An impulse gives a velocity of 14m/s to the heavier block in the direction of lighter block. Find the velocity of center of mass?

for the first which end is at wall and which is at floor ?

2) vel of centre of mass is given by = m1v1 + m2v2 / [m1 + m2 ]

here m1 =10 ,v1= 14 , m2= 4 , v2 =0

substituting values we get

vel of com = 10 m/s ans