Question

diagram of to prove that light travel in straight line​

Answer 1

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.

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Answer 2

$\textbf{Answer:-}$

You can pasś a knitting needle through the holes to confirm if they are in a straight line. Now place a burning candle in front of the board C and look through the pinhole in board A. The flame will be clearly visible. This shows that light travels in a straight line.