Question

The laws of reflection hold true for:

• A. Plane mirrors only
• B. Concave mirrors only
• C. Convex mirrors only
• D. All reflecting surfaces

Answer 1

The correct option is D

All reflecting surfaces

Explanation for correct answer:

In case of option D,

1. The ray that strikes the surface is known as an incident ray and the ray of light that goes back after reflection is known as a reflected ray. An imaginary line perpendicular to the reflecting surface is known as normal.
2. The angle between the incident ray and normal is called the angle of incidence $\left(i\right)$ and the angle between the reflected ray and normal is called the angle of reflection $\left(r\right)$
3. First law of reflection: The angle of incidence is equal to the angle of reflection, $i=r$.
4. Second law of reflection: The incident ray, reflected ray, and normal lie in the same plane, and the incident ray and the reflected ray are on opposite sides of the normal.
5. These three laws hold for all reflecting surfaces. They hold for all mirrors whether it is a plane mirror, concave mirror, or convex mirror, and also for all other reflecting surfaces, which are not mirrors but act like one, for example, water, steel utensils, etc.

Explanation for incorrect answers:

In case of option A,

1. The laws hold true for plane mirrors, but not for only plane mirrors.
2. They are true for other reflecting surfaces also.
3. Thus, this option is incorrect.

In case of option B,

1. The laws hold true for concave mirrors, but not for only concave mirrors.
2. They are true for other reflecting surfaces also.
3. Thus, this option is incorrect.

In case of option C,

1. The laws hold true for convex mirrors, but not for only convex mirrors.
2. They are true for other reflecting surfaces also.
3. Thus, this option is incorrect.

Hence, option D is correct.