question_answer

Why does a ray of light bend towards normal as it passes from air to glass?

Answer:

                We know that \[\mu =\frac{\sin i}{\sin r}=\frac{c}{\upsilon }\] As the speed of light in air is greater than that in glass i.e., \[c>\upsilon \], so\[\sin i>\sin r\] or\[\angle i>\angle r.\] Hence a ray of light bends towards the normal as it passes from air to glass.