Question

Why does a crack in a window pane appear silvery​

Answer 1

Explanation:

When rays of light travelling through the glass, strike the glass-air interface at an angle, greater than the critical angle of glass, they are totally reflected. ... When these reflected rays reach our eyes, then to eyes they appear to come from the crack, which in turns appears to be silvery.

Answer 2

Explanation:

When rays of light travelling through the glass, strike the glass-air interface at an angle, greater than the critical angle of glass, they are totally reflected. ... When these reflected rays reach our eyes, then to eyes they appear to come from the crack, which in turns appears to be silvery.