COMEDK · Physics · 8. Rotational Motion
A mass of \(0.1 \mathrm{~kg}\) is hung at the \(20 \mathrm{~cm}\) mark from a \(1 \mathrm{~m}\) rod weighing \(0.25 \mathrm{~kg}\) pivoted at its centre. The rod will not topple if
- A No other mass is attached to the rod
- B \(0.15 \mathrm{~kg}\) is hung at \(80 \mathrm{~cm}\) mark
- C \(0.15 \mathrm{~kg}\) is hung at \(70 \mathrm{~cm}\) mark
- D \(0.10 \mathrm{~kg}\) is hung at \(70 \mathrm{~cm}\) mark
Answer & Solution
Correct Answer
(C) \(0.15 \mathrm{~kg}\) is hung at \(70 \mathrm{~cm}\) mark
Step-by-step Solution
Detailed explanation
Given, \(m=0.1 \mathrm{~kg}\) Let \(x\) be the position of mass of \(0.1 \mathrm{~kg}\) from its centre and \(x^{\prime}\) be the position of second mass \(m_{2}\) that must be suspended to the other end to prevent the rod from toppling. So,…
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