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प्रश्न
If the speed of a body is doubled, what happens to its kinetic energy?
संख्यात्मक
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उत्तर
K .E, K = `1/2` mv²
If speed is doubled
K.E, K' = `1/2` m (2v2)
or K' = 4 x `1/2` mv2 = 4K
Thus K.E becomes four times.
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