JEE Mains · Physics · STD 11 - 4.2 friction
A block of mass \(m\) slides down the plane inclined at angle \(30^{\circ}\) with an acceleration \(\frac{ g }{4}\). The value of coefficient of kinetic friction will be :
- A \(\frac{2 \sqrt{3}+1}{2}\)
- B \(\frac{1}{2 \sqrt{3}}\)
- C \(\frac{\sqrt{3}}{2}\)
- D \(\frac{2 \sqrt{3}-1}{2}\)
Answer & Solution
Correct Answer
(B) \(\frac{1}{2 \sqrt{3}}\)
Step-by-step Solution
Detailed explanation
\(Mg \sin 30^{\circ}-\mu mg \cos 30^{\circ}= ma\) \(\frac{g}{2}-\frac{\sqrt{3}}{2} \cdot \mu g=\frac{g}{4}\) \(\frac{\sqrt{3}}{2} \mu=\frac{1}{4}\) \(\mu=\frac{1}{2 \sqrt{3}}\)
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