Question

A boy whose mass is 45 kilograms runs up 25 steps with each step 30 centimeters high in just 50 seconds what is the power of boy in horse power

Answer 1

Number of steps = 25

Height of each steps = 30 cm = 0.3 m

Height of 25 steps (H) = 25 × 0.3 = 7.5 m

Mass of the boy (m) = 45 kg

Acceleration due to gravity (g) = 9.8 m/s^2

Work done = m × g × H

Work done = 45 × 9.8 × 7.5

Work done = 3307.5 Joules

$Power = \frac{Work}{Time}$

$Power = \frac{3307.5}{50}$

Power = 66.15 Watts

Power = 0.0887 Horsepower

Hence, the power of the boy is 0.0887 Horsepower.