Q. Two spheres of masses $2M$ and $M$ are initially at rest at a distance $R$ apart. Due to mutual force of attraction, they approach each other. When they are at separation $R/2$, the acceleration of the centre of mass of spheres would be
A) $0\ m/s^{2}$
B) $g\ m/s^{2}$
C) $3g\ m/s^{2}$
D) $12g\ m/s^{2}$
Explanation
(a) Initial acceleration of the system is zero. So it will always remain zero because there is no external force on the system
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.