Which of the following statements is not true if an incident ray of light makes an angle of 30o with the mirror surface?



angle of incidence = 30o

angle of reflection = 60o

angle of incidence = 60o

angle between incident ray and reflected ray = 120o

angle of incidence = 30o

angle of reflection = 60o



angle between incident ray and reflected ray = 120o

we know angle of incidence(i)=angle of reflection(v)

given, The angle between incident ray and reflected ray is 120⁰
given, i+v=120⁰
we know i=v
hence i=v=120degree /2

To determine which statement is not true, we need to understand the relationships between the angles involved in the reflection of light.

When light is incident on a mirror, the angle it makes with the mirror surface is called the angle of incidence. The angle of incidence is always equal to the angle of reflection, which is the angle between the reflected ray and the normal to the mirror surface.

Given that the incident ray of light makes an angle of 30 degrees with the mirror surface, we can identify which statements are true and which is not:

1. Angle of incidence = 30 degrees: This statement is true because it directly corresponds to the given information.

2. Angle of reflection = 60 degrees: This statement is true because the angle of reflection is equal to the angle of incidence, so if the angle of incidence is 30 degrees, the angle of reflection is also 30 degrees.

3. Angle of incidence = 60 degrees: This statement is not true because the given information states that the angle of incidence is 30 degrees, not 60 degrees.

4. Angle between incident ray and reflected ray = 120 degrees: This statement is true because the angle between the incident ray and the reflected ray is always equal to the sum of the angle of incidence and the angle of reflection. In this case, it would be 30 degrees + 30 degrees = 60 degrees.

In summary, the statement that is not true is "angle of incidence = 60o" because the given information states that the angle of incidence is 30 degrees.