A ray of light in air is incident on the surface of a triangular glass prism. At the point of incidence, a normal line is drawn perpendicular to the prism boundary. Define the following angles:

• ${\theta }_{\alpha }$: the angle between the incident ray and the prism boundary
• ${\theta }_{\beta }$: the angle between the incident ray and the normal
• ${\theta }_{\gamma }$: the angle between the refracted ray and the normal
• ${\theta }_{\delta }$: the angle between the refracted ray and the prism boundary

Identify which of these angles is the angle of incidence and which is the angle of refraction.

The refractive index of a specific type of glass is $1.52$. A ray of light travels from inside this glass block out into the air (refractive index $1.00$). The angle of incidence at the glass-air boundary is $28.0^{\circ }$.

Calculate the angle of refraction in the air. Give your answer to one decimal place.

A beam containing both red and blue light is incident on the prism.

(i) State which color, red or blue, experiences a larger refractive index in glass. (ii) Describe how the path of the red light inside the prism differs from the path of the blue light.