Question

if a person is halted at a height 400 m on a mountain peak the work done by the person for 3 hours at the halt position during this 3 hours, if mass is 50 kg and take g as 10 m/s2. *

Answer 1

Given info : a person is halted at a height 400m on a mountain peak. mass of person is 50kg and acceleration due to gravity is g = 10 m/s².

To find : the workdone by the person to reach the halt positon is ...

solution : work done by the person to reach the halt position, W = change in potential energy of the person.

= mgh

here mass of person, m = 50 kg

acceleration due to gravity, g = 10 m/s²

height of halt from the ground, h = 400 m

so, workdone , W = 50 × 10 × 400 =2 × 10⁵ J

therefore the workdone by the person to reach the halt is 2 × 10⁵ J.

also we see , this energy is applied by the person for 3 hrs.

so the power supplied by the person to climb up the halt, P = energy/time

                     = 2 × 10⁵ J/ 3hrs = 2 × 10⁵ /(3 × 3600 s) = 18.5 Watt.