A ball of mass 200 g falls from a height of 5 metres. What is its kinetic energy when it just reaches the ground? (g = 9.8 m/s2)

Mass of the ball, m = 200g = 0.2Kg

Height from which ball is dropped, h = 5m


Initial velocity of the ball, (u) = 0m/s


Acceleration due to gravity, (g) = 9.8m/s2


Therefore, final velocity (v) of the ball is:


V2 = u2 + 2as


By substituting the above given values, we get


V2 = 0 + 2(9.8) (5)


V2 = 98


As we know, kinetic energy,


K.E = 1/2mv2


K.E = 1/2 x 0.2 x 98


K.E = 9.8 J


Hence, the kinetic energy = 9.8 J


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