Question

A block of mass m is connected to another block of mass M by a spring(massless) of spring constant k. The blocks are kept on a smooth horizontal plane.Initially the blocks are at rest and the spring is un stretched.then a constant force F starts acting on the block of mass M to pull it. Find the force on the block of mass m:
(1)mF/M. (2)(M+m)F/m
(3)mF/(m+M). (4)MF/(m+M)

Answer 1

Answer:

Well, the force equations can be written down individually on both the blocks,

On block of mass M

F - kx = Ma

and,

On block of mass m

kx = ma

So, the net force on block of mass m

must be kx which is ma

Clearly, by adding the equations to each other we find out that

a = F/m+M

So then the net force on this block will be

F(net) = mF/m+M

Hope this helps you !