Question

Sushweta has to send a laser signal to Garima. But she finds out that the signal misses Garima by $4^0$. She asks Himanshu to rotate the mirror.

By what angle should Himanshu rotate the mirror so that the signal reaches to Garima? (Himanshu is standing in front of Sushweta and Garima and both of them are on the right and left side of Himanshu respectively )

• A. $2^0$ in clockwise direction
• B. $4^0$ in anti – clockwise direction
• C. $4^0$ in clockwise direction
• D. $2^0$ in anti – clockwise direction

Answer 1

The correct option is D

$2^0$ in anti – clockwise direction

From the figure, it is clear that if you rotate mirror by $1^0$, the light ray will rotate by $2^0$. Hence, we need to rotate mirror by $2^0$ in anti-clockwise direction. By increasing the angle of incidence the reflecting ray moves far from Garima. When the angle of incidence is decreased the ray comes closer to Garima (Hence it is in anticlockwise direction)