Question

A $50$kg person stand on a $25$kg platform. He pulls on the rope which is attached to the platform v is the frictionless pulleys as shown in the figure. The platform moves upwards at a steady rate if the force with which the person pulls the rope is?

• A. $500$N
• B. $250$N
• C. $25$N
• D. None of these

Answer 1

The correct option is B $250$N

Mass of person $=50kg$

Platform mass $=25kg$

Let force be T applied by the person

F.B.D of platform

$2T=N+Mg$

$2T=N+25\ast 10$

$T+N=50\ast 10$

$3T=75\ast 10$

$T=250N$