Place a coin at the bottom of a glass jar containiing water. Now tilt the jar suitably. When viewed at a suitable angle, the coin appears to be floating . Why ?

Explanation

When light rays travel obliquely from an optically denser medium ( water, in this case) to an optically rarer medium ( air, in this case ) , they bend away from the normal at the point of incidence. As a result, the coin appears raised. Therefore, when the jar is tilted suitably and observed at a suitable angle, the coin appears to be floating.