WBJEE · Physics · Work Power Energy
If momentum is increased by \(20 \%\), then kinetic energy increases by
- A \(48 \%\)
- B \(44 \%\)
- C \(40 \%\)
- D \(36 \%\)
Answer & Solution
Correct Answer
(B) \(44 \%\)
Step-by-step Solution
Detailed explanation
Hints: \(\mathrm{K}=\frac{\mathrm{P}^2}{2 m}\) Here \(\mathrm{P}^{\prime}=1.2 \mathrm{P}\) Hence, \(K^{\prime}=\frac{(1.2 \mathrm{P})^2}{2 m}\) \[ \mathrm{K}^{\prime}=1.44 \frac{\mathrm{P}^2}{2 m} \] \(\mathrm{K}^{\prime}=1.44 \mathrm{~K}\) or Percentage increase in…
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