JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
The distance of centre of mass from end \(A\) of a one dimensional rod \(( AB )\) having mass density \(\rho=\rho_{0}\left(1-\frac{ x ^{2}}{ L ^{2}}\right)\,kg / m\) and length \(L\) (in meter) is \(\frac{3 L }{\alpha} m\). The value of \(\alpha\) is \(\ldots \ldots \ldots . .\) (where \(x\) is the distance form end \(A\) )
- A \(3\)
- B \(4\)
- C \(8\)
- D \(2\)
Answer & Solution
Correct Answer
(C) \(8\)
Step-by-step Solution
Detailed explanation
\(dm =\lambda \cdot dx =\lambda_{0}\left(1-\frac{ x ^{2}}{\ell^{2}}\right)\) \(X _{ cm }=\frac{\int xdm }{\int dm _{\ell}}\)…
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