Question

A man is standing on a weighing machine placed in a lift. When stationary his weight is recorded as 40 kg. If the
lift is accelerated upwards with an acceleration of 2 m/s^2, then the weight recorded in the machine will be
(g=10m/s^2)
(a) 32 kg
(C) 42 kg
(b) 40 kg
(d) 48 kg​

Answer 1

Answer:

The answer will be 48 kg

Explanation:

According to the problem the at stationary the weight of the man is 40 kg .

The acceleration of the lift is 2 m/s^2

Now when the lift is at stationary position its upward acceleration is zero.

At this position the force ,f  = mg

When the lift started going upward with acceleration of 2 m/s^2

then, f-mg = ma

Now when the lift is at stationary position the weight of the man is m =40 kg which is the actual weight

Therefore the normal force, f = m(g+a)= 40(10+2)= 480 N

Now we have to find the weight to be stored,

m = f/g = 480/10 = 48 kg