Q7. Give some important term in relation with light.
Ans. Some important terms in relation with light:
- Medium: The substance through which light passes is called a medium.
The Substance can be:
- Transparent Substance: The substance which allows the light to pass through it is called transparent substance.
- Translucent Substance: The substance which allows only a part of light falling on it to pass through is called translucent substance.
- Opaque Substance: The substance which does not allow any light to pass through it is called Opaque substance
- Source of light: An object which emits light is called source of light. All Luminous bodies are the source of light.
- Ray of light: A straight line indicating the path of light by using an arrow is called ray of light.
- A straight line path along which light travels in homogeneous medium is called ray of light.
- Beam of light: A Bundle of light rays moving in the same direction emitted by a source of light is called it beam of light. It can be of three types:
- Parallel beam of light: When the rays which constitutes the beam are parallel to one another, then it is called a parallel beam of light.
- Convergent beam of light: When the light rays are actually meet or appears to meet at a point, then it is called a convergent beam of light.
- Divergent beam of light: When the rays are actually diverged or appear to diverge from a point, then it is called divergent beam of light.