JEE Mains · Physics · STD 11 - 4.2 friction
A given object takes \(n\) times the time to slide down \(45^{\circ}\) rough inclined plane as it takes the time to slide down an identical perfectly smooth \(45^{\circ}\) inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is _______.
- A \(1-\frac{1}{\mathrm{n}^2}\)
- B \(1-n^2\)
- C \(\sqrt{1-\frac{1}{n^2}}\)
- D \(\sqrt{1-n^2}\)
Answer & Solution
Correct Answer
(A) \(1-\frac{1}{\mathrm{n}^2}\)
Step-by-step Solution
Detailed explanation
Case-\(1\) : No friction \(\mathrm{a}=\mathrm{g} \sin \theta\) \(\ell=\frac{1}{2}(\mathrm{~g} \sin \theta) \mathrm{t}_1^2\) \(\mathrm{t}_1=\sqrt{\frac{2 \ell}{\mathrm{g} \sin \theta}}\) Case-\(2\) : With friction \(a=g \sin \theta-\mu g \cos \theta\)…
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