# height of 20 cm. If he takes 30 seconds to climb the stair case, his power is (approximately) 540 W 180 W 360 W 90 W

Total mass of the man and the weight he is carrying = m = 60 + 30 = 90 kg

Total height climbed = h

$\\h=30\times 0.2\\ h=6m$

Total work done by the man = W

$\\W=mgh\\ W=90\times 10\times 6\\ W=5400\ J$

Time taken by the man to cmimb the flight of stairs = t = 30 s

Power of the man = P

$\\P=\frac{W}{t}\\ P=\frac{5400}{30}\\ P=180\ W$

Exams
Articles
Questions