Question

Find the value of ${sin\theta }_{glass}$ below:

Given $n_{air}$ = 1 $n_{glass}$ = 1.5

• A. √3/2
• B. 1/√3
• C. 1/√2
• D. √3

Answer 1

The correct option is B

1/√3

$n_{air}$ $sin{\theta }_{air}$ = $n_{water}$ $sin{\theta }_{water}$ and $n_{water}$ $sin{\theta }_{water}$ = $n_{glass}$ $sin{\theta }_{glass}$

Hence, $n_{air}$ $sin{\theta }_{air}$ = $n_{glass}$ $sin{\theta }_{glass}$

$\Rightarrow$ $sin{\theta }_{glass}$ = $\frac{n_{air}}{n_{glass}}$, $sin{\theta }_{air}$ = $\frac{1}{1.5}$ $\sin$ ${60}^{\circ }$ = $\frac{\sqrt{3}}{2}$ $\times$ (1.5) = $\frac{1}{\sqrt{3}}$