Question

In order to raise a mass of 100kg `a` of mass 60kg fastens `a` rope to it and passes the rope over a smooth pulley. He climbs the rope with acceleration `5g//4` relative to the rope. The tension in the rope is: Take `g=10m//s^(2)`
A. 1432N
B. 928N
C. 1219N
D. 642N

Answer 1

Correct Answer - C
Let `T` be the tension in the rope and `a` the acceleration of rope. The absolute acceleration of mass is therefore `((5g)/(4)-a)` . Equations of motion for mass and man gives:
`T-100g=100a` (i)
`T-60g=60((5g)/(4)-a)` (ii)
Solving (i) and (ii), we get, `T=1218.75N=1219N`
`10=(1)/(2)(1.25)t_(2)` implies `t=4sec` .