List of top Physics Questions on Centre of mass asked in AP EAPCET

Two particles of masses $m_1$ and $m_2$ ($m_1 > m_2$) are separated by a distance 'd'. When the positions of the two particles are interchanged, the shift in the centre of mass is:

Two identical particles move towards each other with velocities $2V$ and $V$ respectively. The velocity of the center of mass of this system is: