A particle of mass 1 kg is projected upwards with velocity 60 m/s. Another particle of mass 2 kg is just dropped from a certain height. Find out the acceleration and the velocity of COM after 2 s when neither of the particles has collided with the ground.
We know that,
a = [m1a1+m2a2][m1+m2] and
u =[m1u1+m2u2][m1+m2]
So,
a = [m1a1+m2a2][m1+m2]
=[(1)∗(−10)+2∗(−10)]3
=−10m/s2
u =[m1u1+m2u2][m1+m2]
=[(1)∗(60)+(2)∗(0)]3 = 20m/s
From the above observation we conclude that, acceleration of the centre of mass will be −10m/s2 and velocity of the centre of mass will be 20m/s.