Does light travel in a straight line? Describe an activity in support of your answer.

Explanation

Yes, light does travel only in a straight line or rectilinear path.

We can understand it through an activity using a candle or a rubber tube that can bend at any angle.

Step 1. Fix a lighted candle on a table. and take a rubber tube.

Step 2. Stretch the rubber tube straight and look through it at the flame of the candle with one eye (keeping the other eye closed) as shown in figure (a)

Step 3. We will find that when the rubber tube is straight, we can see the light of a candle flame through it.

Step 4. Now, bend the rubber tube a little and look through it at the candle flame again. We cannot see the light of a candle flame through a bent rubber tube as shown in figure (b).

From this observation, we conclude that light travels in a straight line.