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ScienceCLASS 9CBSE

answered 27 Mar 2026

A ball is dropped from a height of 10 m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back? (g = 10 m s–2).

A.VERIFIED ANSWERfact-checked by tutors

Soln:

mgh=m×10×10= 100m joules

when 40% energy is reduced remaining energy will be 60mjoules Hence 60-m×10×h

H= -6m

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