Question

An Incident ray makes an angle of 55° with a plane. Then the value of incident angle is ?
A:55°
B:35°
C:45°
D:110°​

Answer 1

Answer:

D. 110°

Explanation:

Further on reflection, it makes the same angle i.e. angle of reflection is equal to angle of reflection. Hence, as angle of incidence is 55∘ angle of reflection too is 55∘ and the angle between the incident ray and the reflected ray is 55∘+55∘=110∘

Answer 2

The angle of reflection is

55

∘

and angle between the incident ray and the reflected ray is

110

∘

.

Explanation:

Angle of reflection is measured between the incident ray and the angle which it makes with the normal at the point where incident ray strikes the mirror surface.

Further on reflection, it makes the same angle i.e. angle of reflection is equal to angle of reflection.

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Hence, as angle of incidence is

55

∘

angle of reflection too is

55

∘

and the angle between the incident ray and the reflected ray is

55

∘

+

55

∘

=

110

∘

.