Question

A ray of light strikes a plane mirror at an angle of 40 to the mirror surface. What will be the angle of reflection?

Answer 1

Answer:

The answer is 50

Explanation:

The question states that the incident ray is at an angle of 40 with the MIRROR SURFACE .

So, 90 - 40 = 50  

angle of incidence = 50

Then by law of reflection ,

angle of reflection = angle of incident

So, angle of reflection = 50

Answer 2

The angle of reflection is 50°.

The incident ray strikes the plane mirror at an angle of 40° to the mirror surface.

• Now, we know that angle of incidence is the angle between the incident ray and the normal.

$\therefore \: \angle i = {90}^{ \circ} - {40}^{ \circ}$

$\implies \: \angle i = {50}^{ \circ}$

• Again, as per the laws of reflection, the angle of incidence is equal to the angle of reflection.

$\boxed{ \implies \: \angle i = \angle r = {50}^{ \circ} }$

So, angle of reflection is 50°.