Question

Incident ray and reflected ray (for a plane surface) enclose an angle of 1200 .At what angle is the incident ray inclined with the reflected surface?​

Answer 1

Answer:

Explanation:

Given

Incident ray and reflected ray (for a plane surface) enclose an angle of 120⁰

To find

At what angle is the incident ray inclined with the reflected surface?​

Solution

According to the law of reflection,

angle of incidence = angle of reflection

=> ∠i = ∠r

We know that

Incident ray and reflected ray (for a plane surface) enclose an angle of 120⁰

=> ∠i + ∠r = 120⁰ (∠i = ∠r)

=> 2∠i = 120⁰

=> ∠i = 60⁰

Hence,

∠i = ∠r = 60⁰

The angle to which the incident ray is inclined with the reflected surface = 90⁰ - ∠i

= 90⁰ - 60⁰

= 30⁰

Ans

The incident ray inclined with the reflected surface at an angle of 30⁰.