Question

The ray of light travels from an optically denser to rarer medium. The critical angle for the two media is $C$. The maximum possible angle of deviation of the ray will be :

• A. $\frac{\pi }{2}-C$
• B. $\pi -2C$
• C. $2C$
• D. $\frac{\pi }{2}+C$

Answer 1

Answer: (B)

$\pi -2C$

The maximum possible angle of deviation occurs when it undergoes $Total$ $Internal$ $Reflection$ as shown in the figure.

So, from figure $C+C+\delta =\pi$

$\Rightarrow \delta =\pi -2C$