Question

A body of mass 2 kg is hung on a spring balance mounted vertically in a lift if the lift Descent with an acceleration equal to the acceleration due to gravity G the reading on the spring balance will be

Answer 1

A body of mass 2kg is hung on a spring balance mounted vertically in a lift . now the loft descent with an acceleration equation to acceleration due to gravity g.

lift is descending with acceleration g, means body is in non - Inertial frame of reference ,we know Newton's law of motion can't be applied in non - inertial frame of reference. so just use the concept of Psuedo force to make it inertial frame of reference.

so, net reading on spring balance = m(g - a)
here, a = g
so, reason on spring balance = 0

Answer 2

Answer:

m=2 kg

acc.lift downward direction=g

let reading = N

N=ma+mg

ma= mg-N

mg= mg-N. (a=g)

N= mg - mg

N=0