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3 years ago

5

A 170-lb man carries a 10-lb can of paint up a helical staircase that encircles a silo with radius 15 ft. if the silo is 40 ft h

igh and the man makes exactly two complete revolutions, how much work is done by the man against gravity in climbing to the top? ft-lbs

1 answer:

goldenfox [79]3 years ago

4 0

Work done against the gravity = Total weight*Vertical distance covered.

Total weight = 170+10 = 180 lb
Vertical distance covered = 40 ft

Therefore,

Work done = 180*40 = 7200 lb-ft

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