Wave Mechanics Question 878
Question: A wave has velocity u in medium P and velocity 2u in medium Q. If the wave is incident in medium P at an angle of 30° then the angle of refraction will be
[J & K CET 2005]
Options:
A) 30°
B) 45°
C) 60°
D) 90°
Show Answer
Answer:
Correct Answer: D
Solution:
$ v=\frac{\sin i}{\sin r}=\frac{v _{1}}{v _{2}} $
Therefore $ \sin r=\sin 30{}^\circ \times \frac{2u}{u}\Rightarrow \sin r=\frac{1}{2}\times 2\times 1 $
$ \Rightarrow r=90{}^\circ $
BETA
