Question

3 blocks abc of mass 4 kg 2 kg and one kg respectively are in connect on fashion show if a force of 40 newton is applied on 4 kg club then the contact force between a and b is

Answer 1

the acceleration due to force 14N=

F=ma
F/m =a
14/(4+2+1)
14/7
=2m/s2

the contact force between A and B is used to move the bodies B and C only.
F=ma
F=(2+1)2
F=3×2
=6N