Question

A ray of light travelling in the direction $\frac{1}{2}(\hat{i}+\sqrt{3}\hat{j})$ is incident on a plane mirror. After reflection, it travels along the direction $\frac{1}{2}(\hat{i}-\sqrt{3}\hat{j})$. The angle of incidence is ${30}^o$

• A. True
• B. False

Answer 1

The correct option is A True

as there is no change in $i$ component , y-axis is the normal to the mirror .
the y-axis component is $\frac{\sqrt{3}}{2}$ it is cosine of angle ${30}^{\circ }$ hence the angle of incidence is ${30}^{\circ }$
option $A$ is correct