**Question:**

**A particle is released on a vertical smooth semicircular track from point $X$ so that $O X$ makes angle $\theta$ from the vertical (see figure). The normal reaction of the track on the particle vanishes at point $Y$ where $O Y$ makes angle $\phi$ with the horizontal. Then:**

$\sin \phi=\cos \phi$

$\sin \phi=\frac{1}{2} \cos \theta$

$\sin \phi=\frac{2}{3} \cos \theta$

$\sin \phi=\frac{3}{4} \cos \theta$

Question of from chapter.

JEE Main Previous Year April 19, 2014

Correct Option: 3

**Solution:**

(3)

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