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Question
Calculate the change in the Kinetic energy of a moving body if its velocity is reduced to 1/3rd of the initial velocity.
Solution
Let the inital kinetic energy be E1=E
Now, the kinetic energy is directly proportional to the square of the velocity
K.E ∝ v2
∴ Final kinetic energy =E2=`1/9E`
Hence, the change in kinetic energy is given as,
`ΔE=E_1-E_2`
`Delta E=E-1/9E`
`Delta E=8/9E`
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