WBJEE · Physics · Rotational Motion
"Two particles \(A\) and \(B\) are moving as shown. in the figure.
Their total angular momentum about the point \(O\) is
- A \(9.8 \mathrm{kg} \mathrm{m}^{2} / \mathrm{s}\)
- B zero
- C \(52.7 \mathrm{kg} \mathrm{m}^{2} / \mathrm{s}\)
- D \(37.9 \mathrm{kg} \mathrm{m}^{2} / \mathrm{s}\)
Answer & Solution
Correct Answer
(A) \(9.8 \mathrm{kg} \mathrm{m}^{2} / \mathrm{s}\)
Step-by-step Solution
Detailed explanation
Total angular momentum about \(O\) is given as, \[ \begin{aligned} \mathbf{L} &=\mathbf{L}_{1}+\mathbf{L}_{2}=m_{1} V_{1} I_{1}+m_{2} V_{2} I_{2} \\ &=-6.5 \times 2.2 \times 1.5+3.1 \times 3.6 \times 2.8 \\ &=-21.45+31.248=9.8 \mathrm{kgm}^{2} / \mathrm{s} \end{aligned} \]
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