JEE Mains · Physics · STD 11 - 4.2 friction
The time taken by an object to slide down \(45^{\circ}\) rough inclined plane is \(n\) times as it takes to slide down a perfectly smooth \(45^{\circ}\) incline plane. The coefficient of kinetic friction between the object and the incline plane is
- A \(\left( {1 - \frac{1}{{{n^2}}}} \right)\)
- B \(1+\frac{1}{ n ^2}\)
- C \(\sqrt {\left( {1 - \frac{1}{{{n^2}}}} \right)} \)
- D \(\sqrt {\frac{1}{{1 - {n^2}}}} \)
Answer & Solution
Correct Answer
(A) \(\left( {1 - \frac{1}{{{n^2}}}} \right)\)
Step-by-step Solution
Detailed explanation
(a)\(\mu = \tan \theta \left( {1 - \frac{1}{{{n^2}}}} \right)\) \( = 1 - \frac{1}{{{n^2}}}\) [As \(\theta = 45^\circ \)]
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