Answer:
Take three cardboards of similar size and make a hole in the centre of each. Make sure that the size and position of the hole is the same in each cardboard. Now put the three cardboards in vertical position with the help of bricks in such a way that the holes in the three cardboards are in a straight line. Place a lighted candle in front of the cardboard no. 1 as shown in Fig. Look through the hole of the last cardboard no. 3. 
The flame can be seen clearly through the holes. When one of the cardboards is slightly raised, no flame can be seen. This shows that light travels in a straight line. No flame can be seen when the holes of the three cardboards are not in a straight line because light can-not bend.
You need to login to perform this action.
You will be redirected in
3 sec
