Q20 of 146 Page 163

A man weighing 500 N carried a load of 100 N up a fighter of stairs 4 m high in 5 seconds. What is the power?

Given, weight of the man = 500N

Weight of the load = 100N


Total weight = 500 + 100 = 600N


Height (vertical distance) = 4m


Work done = total weight x vertical distance


Work done = 600 x 4


Work done = 2400 J


Power = Work done/time


= 2400/ 5


= 480W


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