For the system shown in the figure, if F2 and F3 are forces acting on the masses m2 and m3 respectively, then the correct relation between the forces is (Assume that the blocks are connected by inextensible strings and the surface is frictionless)
F1=(m1+m2+m3)a
⇒a=F1m1+m2+m3
Now, draw the FBD of mass m3 alone
F3=m3a−−(1)
Substituting a in equation (1), we get
F3=m3F1m1+m2+m3