How does the light have to enter the glass?

(a) To produce a large amount of bending?

(b) For no refraction to happen?

A vertical ray of light strikes the horizontal surface of some water:

(a) What is the angle of incidence?

(b) What is the angle of refraction?

How is the reflection of light ray from a plane mirror different from the refraction of light ray as it enters a block of glass?

How can you bend light away from the normal?

How must light travel out of a substance if it is not going to be refracted?