Question

A man of mass 50 kg is standing in an elevator elevator is moving up with an acceleration g by 3 then work done by normal reaction of law of elevator elevator on man when elevator mod by a distance 12 metre is

Answer 1

Answer:

1800 Joules

Explanation:

Given :

m=50 kg

g=3m/s

h=12m

W=mgh

= 50*3*12

1800 Joules

Hope this helps...

Answer 2

Work done by normal reaction of law of elevator is 8000 J

Explanation:

Let N be the normal reaction on the man in the elevator.

Acceleration=g/3

m=50 kg

so, as the lift moves up,

N-mg=ma

or, N=m(g+a)

or, N= 50(10+10/3)

or, N=2000/3

Now, Distance(S)= 12 m

so work done= N*S

                      = 2000/3 * 12 joule

                      = 8000 joule