Question

Q21. a man whose mass is 50 kg climbs up 30 steps of a stair in 30 s. if each step is 20 cm high, calculate the power used in climbing stairs.

Answer 1

$Power consumed = \frac{Wok done}{Total Time Taken}$

Given m = 50 kg, d = 0.20 x 30 = 6 metres

Calculating work
W = F x d
    = ( m x g) x d
    = ( 50 x 9.8 ) x 6
    = 2940 Joules

Hence, Power consumed is = ( 2940/30 ) = 98 Jouules/second