Solution:
Distance between bullet and block at this instant is .
Distance of CM from bullet
Similarly, distance of CM from block
Hence, option (4) is correct.
In a free space, a rifle of mass M shoots a bullet of mass m at a stationary block of mass M at a distance D away from it. When the bullet has moved through a distance d towards the block, the centre of mass of the bullet-block system is at a distance of
Distance between bullet and block at this instant is .
Distance of CM from bullet
Similarly, distance of CM from block
Hence, option (4) is correct.