A force F is applied horizontally to a block A of mass m1 which is in contact with a block B of mass m2, as shown in the figure. If the surfaces are frictionless, the force exerted by A on B is equal to
m2Fm1+m2
Acceleration of the system, a=Fm1+m2
Now, the force exerted by A on B is responsible for the acceleration of block B and is given by F′=m2a=m2Fm1+m2.
Hence, the correct choice is (d).