Question

how can you define light in Physics? give an experiment to show that light always travel in straight line.​

Answer 1

Answer:

In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not. In this sense, gamma rays, X-rays, microwaves and radio waves are also light. ... The absorbed energy of the EM waves is called a photon, and represents the quanta of light.

Two experiments are used to demonstrate how light travels in straight lines. In the first example, the presenter arranges three pieces of card, with holes in, in an uneven line. The light stops and cannot travel through all three cards. When she arranges the holes in a straight line, the light can travel through.

Hope this helps u :D

Answer 2

Description of Light

Light is an individual form of energy which enable us to see the object. It fall on the surface of the object are opposed to us.

The Sun is the ultimate source of of light energy on the earth.

All the object are categories into two types on the basis of emitting light , these are listed below :-

• Luminous Objects
• Non - Luminous Objects

Points to Remember

The Speed of light in vacuum is 3 × ${\bold{10}^{8}}$ per Second.

It is also considered that the speed of light in air is 3 × ${\bold{10}^{8}}$ per Second.

The light rays was always travel in the straight line.

Required Experiment

Experiment to show light rays always travel in straight line :-

1. Take 3 cardboard, make hole at similar height.

2. Keeping apart similar distance to one another. made it stand at a similar height .

3. A Burning candle placed at the stand at a fixed height so that light rays pass through the three holes in the cardboard .

4. From last cardboard we can see the burning candle.

5. If any cardboard displace from its position then the burning candle does not appear to the eyes .

6. So this shows that the light is always travel in a straight line.