Two blocks of masses `6 kg` and `4 kg` are attached to the two ends of a massless string passing over a smooth fixed pulley. if the system is released, the acceleration of the centre of mass of the system will be

Options

A. `g`, vertically downwards
B. `g/5`, vertically downwards
C. `g/25`, vertically downwards
D. zero

Answer

C

Explanation

`a=(6-4)/(6+4)g=g/5, a_(CM)=(-6xxa+4a)/(6+4)=-a/5=-g/25`