6.27 A bolt of mass 0.3 kg falls from the ceiling of an elevator moving down with an uniform speed of 7 m s–1. It hits the floor of the elevator (length of the elevator = 3 m) and does not rebound. What is the heat produced by the impact ? Would your answer be different if the elevator were stationary ?
6.27 A bolt of mass 0.3 kg falls from the ceiling of an elevator moving down with an uniform speed of 7 m s–1. It hits the floor of the elevator (length of the elevator = 3 m) and does not rebound. What is the heat produced by the impact ? Would your answer be different if the elevator were stationary ?
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1 Answer
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6.27 Mass of the bolt, m = 0.3 kg, Height of the elevator, h = 3 m
Since the bolt did not rebound, the entire potential energy got converted into heat.
The potential energy of the bolt = mgh = 0.3 x 9.8 x 3 J = 8.82 J
The heat produced will remain same even if the lift is stationary, since g = constant
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