A ball is dropped from rest and falls to the floor. The initial gravitational potential energy of the ball-Earth-floor system is 10 J. The ball then bounces back up to a height where the gravitational potential energy is 7 J. What was the mechanical energy of the ball-Earth-floor system the instant the ball left the floor? (A) 0J (B) 3J (C) 7J (D) 10J

Question

Physics

Ali Clements

7 August, 18:42

A ball is dropped from rest and falls to the floor. The initial gravitational potential energy of the ball-Earth-floor system is 10 J. The ball then bounces back up to a height where the gravitational potential energy is 7 J. What was the mechanical energy of the ball-Earth-floor system the instant the ball left the floor? (A) 0J (B) 3J (C) 7J (D) 10J

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Answers (1)

Know the Answer?

Arden · Answer 1

C is the right option

Explanation:

The ball looses energy in the rebound due to ball deformation, heat loss from bounce. Total mechanical energy is not conserved so mechanical energy as it bounces of the floor is equal to transformed potential energy at maximum height of second bounce which is 7j.