Physics
A ball of mass 0.5 kg slows down from a speed of 5ms-1 to that of 3ms-1. Calculate the change in kinetic energy of the ball.
Work, Energy & Power
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Answer
Given,
Mass = 0.5 kg
Initial velocity = 5 m / s
Final velocity of the ball = 3 m / s
Kinetic energy = 1 / 2 × mass × (velocity)2
Substituting the values in the equation we get,
Final kinetic energy,
So, change in the kinetic energy of the ball = 2.25 J – 6.25 J = – 4J
Hence, there is a decrease in the kinetic energy of the ball by 4J.
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