Question

A block of mass M is pulled along a horizontal frictionless surface by a rope of mass M/2. If a force 2Mg is applied at one end of the rope find the force which the rope exerts on the block

Answer 1

ANSWER

Consider the system as a whole

A block of mass M and a rope tied to it of mass m pulled by a force P,

The only external force

The system will accelerate due to the action of the force , all accelerating with same acceleration

Acceleration of the system =

Totalmass

Totalexternalforce

a =

m+M

P

Therefore acceleration of the block of mass M will also be a

Net force on it = mass x acceleration

This force is force of the rope on the block

Hence F = m+MPM

$hope \: this \: helps \: you$