Q116 / 150 · MHT CET 2022 (05 Aug Shift 1) · Physics
A $4 \mathrm{~kg}$ mass and a $1 \mathrm{~kg}$ mass are moving with equal energies. The ratio of the magnitude of their linear momenta is
- Correct answerA$2: 1$
- B$4: 1$
- C$1: 2$
- D$1: 1$
Solution
The correct option is (A).
Kinetic Energy $\mathrm{K}$ and momentum $p$ are related as:
$\mathrm{K}=\frac{\mathrm{p}^2}{2 \mathrm{~m}}$
Therefore,
$P=\sqrt{2 K m}$
The ratio of momentum for $4 \mathrm{~kg}$ mass and $1 \mathrm{~kg}$ mass moving with equal kinetic energy $\mathrm{K}$ is
$\frac{\mathrm{p}_{4 \mathrm{~kg}}}{\mathrm{p}_{1 \mathrm{~kg}}}=\sqrt{\frac{2 \mathrm{~K}(4 \mathrm{~m})}{2 \mathrm{~K}(\mathrm{~m})}}=\frac{2}{1}$
Hence, the correct answer is option: 'A'.