A body of mass 2 kg has momentum 10 kg·m/s. Its kinetic energy is: MCQ with Answer and Explanation

A body of mass 2 kg has momentum 10 kg·m/s. Its kinetic energy is:
A. 12.5 J
B. 25 J
C. 50 J
D. 100 J
Answer: Option A
Solution (By JKSSB Mock Tests)
KE = p²/(2m) = (10)²/(2×2) = 100/4 = 25 J. Wait, recalculate: 100/4 = 25 J. Option B is correct. KE = p²/2m relates momentum and kinetic energy. Memory tip: When given momentum, use KE = p²/2m instead of finding velocity first. Efficient calculation method for competitive exam time constraints.

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