Two bodies of different masses of 2 kg and 4 kg are moving with velocities 2 m/s and 10 m/s towards each other due to mutual gravitational attraction. What is the velocity of their centre of mass?

Options

A. 5 m/s
B. 6 m/s
C. 8 m/s
D. zero

Answer

D

Explanation

As gravitational force of attraction are mutual, centre of mass is not affected (in the absence of external force) velocity of centre of mass is zero.