The system shown in the figure is in equilibrium at rest. The spring and string are massless Now the string is cut. Find the acceleration of the blocks just after the string is cut.

Explanation

Under equilibrium of mass m
T= mg.
Now the string is cut, Therefore
T= mg force is decreased on mass m upwards and downwards on mass 2m.
`:.` Acceleration of `m=(mg)/(m)=g`
Acceleration of `2m=(3mg-2mg)/(2m)=(g)/(2)`