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JEE Mains · Physics · STD 11 - 7. gravitation
If the earth suddenly shrinks to \(\frac{1}{64}\) th of its original volume with its mass remaining the same, the period of rotation of earth becomes \(\frac{24}{ x } h\). The value of \(x\) is \(.......\)
- A \(8\)
- B \(4\)
- C \(2\)
- D \(16\)
Answer & Solution
Correct Answer
(D) \(16\)
Step-by-step Solution
Detailed explanation
From conservation of angular momentum \(\frac{2}{5} MR ^2 \omega_1=\frac{2}{5} M \left(\frac{ R }{4}\right)^2 \omega_2\) \(\Rightarrow MR ^2 \omega_1=\frac{ MR ^2}{16} \omega_2\)…
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