alleryStart learning →Two bodies have equal momentum. Which one has the LARGER kinetic energy?
AThe heavier one
BThe lighter one
CBoth have equal kinetic energy
DIt depends only on velocity direction
Answer & Solution
Correct answer: B. The lighter one
1. Momentum p = m·v and kinetic energy KE = ½·m·v².
2. Rewriting KE in terms of momentum: KE = p² / (2·m).
3. With the same p, KE is inversely proportional to m.
4. Smaller mass therefore gives a larger kinetic energy for the same momentum.
5. So the lighter body has the larger kinetic energy.
_Source: Selina Concise Physics ICSE Class 9, Ch 3 'Laws of Motion' (aplustopper.com extract)_
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