Q17 of 49 Page 11

A crane lifts a car upto a certain height in 1 minute. A second crane lifts the same car upto the same height in 2 minutes. Which crane supplies the greater power? Which crane consumes more fuel?

The two cranes do the same amount of work, i.e.,
W = mass of the car × acceleration due to gravity × height of the lifted car.
Hence both cranes consume the same amount of fuel. The first crane does the same amount of work in half the time than the second crane. Hence the first crane supplies two times more power than the second crane.

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