Question

.A girl of weight 500 N runs up a flight of stairs in 10 sec . The vertical height of the stairs is 5 m. What is the average power developed by the girl​

Answer 1

Given: A girl of weight 500 N runs up a flight of stairs in 10 sec . The vertical height of the stairs is 5 m.

To find: The average power developed by the girl​.

Solution:

• The formula of power is given by,

        $P = \frac{W}{t}$

• Here, P is the power, W is the work done by the girl and t is the time period.
• However, the formula of work is given by,

        $W = F * d$

• Here, F is the force applied and d is the displacement of the girl.
• On replacing the terms of the work formula with the values given in the question,

        $W = 500 N * 5 m$

             $= 2500 Nm$

• On replacing the terms of the power formula with the values given in the question,

       $P = \frac{2500Nm}{10s}$

           $= 250W$

Therefore, the average power developed by the girl is 250 W.