Question

The reflective surface is given by y $=$ 2 sinx. The reflective surface is facing positive x-axis. What is the least values of co ordinate of the point where a ray parallel to positive x axis becomes parallel to positive y axis after reflection 2.

• A. $(\frac{\pi }{3},\sqrt{3})$
• B. $(\frac{\pi }{2},\sqrt{2})$
• C. $(\frac{\pi }{3},\sqrt{2})$
• D. $(\frac{\pi }{4},\sqrt{2})$

Answer 1

The correct option is A $(\frac{\pi }{3},\sqrt{3})$

$m\left(L_1\right)=2cos{x}_o$

$m\left(N\right)=\frac{+1}{2cos{x}_o}$

$m\left(N\right)=\frac{+1}{2cos{x}_o}=1$

$cos{x}_o=\frac{1}{2}$

$x_o=\frac{\pi }{3}$

$y=2sin\left(\frac{\pi }{3}\right)=\sqrt{3}$