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Question
Define the following terms used in the study of reflection of light by drawing a labelled ray-diagram:
- Incident ray
- Point of incidence
- Normal
- Reflected ray
- Angle of incidence
- Angle of reflection
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Solution
- Incident ray: The ray of light which falls on the mirror surface is called the incident ray.
- Point of incidence: The point at which the incident ray falls on the mirror is called the point of incidence.
- Normal: The normal is a line at right angles to the mirror surface at the point of incidence.
- Reflected ray: The ray of light which is sent back by the mirror is called the reflected ray.
- Angle of incidence: The angle of incidence is the angle made by the incident ray with the normal at the point of incidence.
- Angle of reflection: The angle of reflection is the angle made by the reflected ray with the normal at the point of incidence.
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