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प्रश्न
When the speed of a moving object is doubled, then its kenetic energy ______.
पर्याय
remains the same
decreases
is doubled
becomes four times
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उत्तर
When the speed of a moving object is doubled, then its kenetic energy becomes four times.
Explanation:
Kinetic energy (k) ∝ (velocity v)2
Now `("k'")/"k"=(2"v")^2/("v")^2`
⇒ k' = 4k
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