A body of mass m is resting on another body of mass M as shown in the

1.	A body of mass m is resting on another body of mass M as shown in the fig. The coefficient of static friction between the two surface is μ. There is no friction between mass M and horizontal surface. What minimum force F should be applied to M so that the load m will just begin to slide along it.
Answer» Acceleration a = {F}/{m + M} Force experienced by m' = ma = {mF}/{M + m} The body of mass m will just begin to slide when the force experienced by 'm' just exceeds μmg. i.e., {Fm}/{M + m} = μmg ⇒ F = μg.(M + m)

A body of mass m is resting on another body of mass M as shown in the fig. The coefficient of static friction between the two surface is μ. There is no friction between mass M and horizontal surface. What minimum force F should be applied to M so that the load m will just begin to slide along it.

Answer»

Acceleration a = {F}/{m + M}

Force experienced by m' = ma = {mF}/{M + m}

The body of mass m will just begin to slide when the force experienced by 'm' just exceeds μmg.

i.e., {Fm}/{M + m} = μmg

⇒ F = μg.(M + m)