Question

The angle between incident ray and reflected ray is ${90}^o$. Find the angle of reflection.

• A. ${90}^o$
• B. ${45}^o$
• C. ${30}^o$
• D. Can't be predicted

Answer 1

Answer: (B)

${45}^o$

According to law of reflection

The angle of incidence $=$ the angle of reflection $=\theta$, say.

So, the angle between the incident and the reflected ray$=\theta +\theta =2\theta$

As per given condition, $2\theta ={90}^0$

or, $\theta ={45}^0$

The angle of reflection is ${45}^0$