Two plane mirrors are inclined at an angle$ heta$. It is found that a ray incident on one mirror at any angle is rendered parallel to itself after reflection from both the mirrors. The value of $ heta\ $is

Question

Two plane mirrors are inclined at an angle$	heta$. It is found that a ray incident on one mirror at any angle is rendered parallel to itself after reflection from both the mirrors. The value of $	heta\ $is

Dr. Abubacker · Accepted Answer

(c) Incident ray and finally reflected ray are parallel to each other means $\delta\  = \ 180{^\circ}$
From $\delta\  = \ 360{^\circ} - 2	heta$
$\Rightarrow \ \ \ \ \ \ \ \ \ 180{^\circ}\  = \ 360{^\circ} - 2	heta$
$\Rightarrow \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 	heta\  = \ 90{^\circ}$
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Q. Two plane mirrors are inclined at an angle$\theta$. It is found that a ray incident on one mirror at any angle is rendered parallel to itself after reflection from both the mirrors. The value of $\theta\ $is

Explanation

Reviewed by Dr. Abubacker

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