A boy of mass 50kg,climb a hii of 5m high,calculate the power use

{1}when the boy used the total time of 20s.[g:10m/s]

125J

Correct.

P = F * d/t = Mg * d/t = 500 * 5/20 = 125 J/s = 125 Watts.

To calculate the power used by the boy, we need to use the formula:

Power = Work / Time

First, let's calculate the work done by the boy. The work done is equal to the change in potential energy:

Work = Mass x Gravity x Height

Given:
Mass (m) = 50 kg
Gravity (g) = 10 m/s^2
Height (h) = 5 m

Work = 50 kg x 10 m/s^2 x 5 m
= 2500 kg m^2/s^2

Now, we can calculate the power by dividing the work by the time:

Power = Work / Time

Given:
Time (t) = 20 s

Power = 2500 kg m^2/s^2 / 20 s
= 125 kg m^2/s^3

Therefore, the power used by the boy when he used a total time of 20 seconds is 125 kg m^2/s^3.