Question

A boy of mass 40 kgclimbs 20 steps of a staircase, each measuring 20 cmhigh in 30 s. Calculate the power developed by the boy. [Take g=10 m/s2]​

Answer 1

Answer:

POWER = work/time

work done in lifting an object to height is stored as gravitational potential( it is the work done in lifting a object of mass m to height) = mgh

t = 30 second

now

20 steps of staircase

so h = 20×20 = 400 cm = 4 m

p = 40×10×4/30

p = 53.333....