If the kinetic energy of a body is increased by 300%, its momentum will increase by: MCQ with Answer and Explanation

If the kinetic energy of a body is increased by 300%, its momentum will increase by:
A. 200%
B. 300%
C. 150%
D. 100%
Answer: Option D
Solution (By JKSSB Mock Tests)
The relationship between kinetic energy (K) and momentum (p) is K = p² / 2m. If K is increased by 300%, the new kinetic energy K' = K + 3K = 4K. Since p = √(2mK), the new momentum p' = √(2m × 4K) = 2√(2mK) = 2p. The momentum has doubled. Percentage increase = [(2p - p)/p] × 100 = 100%.

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Correct Answer: Option C


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