Question

A young boy of mass 45000 g runs up a staircase of 83 steps in 27 s. If the height
of each step is 15 cm. Calculate his power. Take g = 10 m/s2​

Answer 1

Given:

Mass of body (m) = 45000 g = 45 kg

Height of each step = 15 cm = 0.15 m

Height of staircase i.e of 83 steps (h) = 83 × 0.15 = 12.45 m

Time (t) = 27 sec

To calculate:

Power = P

We know,

Power (P) = Potential Energy / Time

Now to calculate potential energy,

Potential energy = mgh

= 45 × 10 × 12.45

Therefore,

P = (45 × 10 × 12.45) / 27

P = 207.5 Watt

______________________

Power is a measure of amount of work done in given time. We know conservative force gives rise to potential energy. Here, work done by the young boy is stored in the form of potential energy. Therefore, work done = potential energy.

P = Work done (W) / t

P = E (potential energy) / t

Answer 2

Answer:

Given:

Mass of body (m) = 45000 g = 45 kg

Height of each step = 15 cm = 0.15 m

Height of staircase i.e of 83 steps (h) = 83 × 0.15 = 12.45 m

Time (t) = 27 sec

To calculate:

Power = P

We know,

Power (P) = Potential Energy / Time

Now to calculate potential energy,

Potential energy = mgh

= 45 × 10 × 12.45

Therefore,

P = (45 × 10 × 12.45) / 27

P = 207.5 Watt

______________________

Power is a measure of amount of work done in given time. We know conservative force gives rise to potential energy. Here, work done by the young boy is stored in the form of potential energy. Therefore, work done = potential energy.

P = Work done (W) / t

P = E (potential energy) / t

Explanation:

Hope this answer will help you.