A ball is gently dropped from a height of 20 m. If its velocity increa – InterviewSolution

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1.	A ball is gently dropped from a height of 20 m. If its velocity increases uniformly at the rate of 10ms-1 with what velocity will it strike the ground? After what time will it strike the ground?
Answer» Distance ball covers, S = 20 m acceleration, a = 10Kmh^-1 = 10 m/s initial velocity, u = 0 (at rest) When ball strikes, its final velocity, According to 3rd law of motion v² = u² + 2as v² = 0 + 2(10)(20) v = 20 m/s. According to 1 st Law of motion v = u + at Time taken by ball to strike the ground, t, 20 = 0 + 10 (t) ∴ t = 2s ∴ 2s is required to ball for striking the ground and velocity is 20 m/s

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