Part A) Coloured light (shown with a red arrow) is incident on a 30 degree glass prism at an angle of incidence of 90 degrees. The glass has a refractive index of 1.556 at 515 nm (green) and 1.541 at 633 nm (red). This dispersion will result in the two colours being split as it exits the prism. What will be the angle between these two rays? Give you solution in degrees to 3 d.p. Part B) A pair of binoculars has been treated with an anti-reflection coating designed to work best at 500 nm. The coating is made of a material with a refractive index of 5.98 at this wavelength. What is the minimum thickness the coating could be? Give your solution in nm to 3 s.f.

Part A) Coloured light (shown with a red arrow) is incident on a 30 degree glass prism at an angle of incidence of 90 degrees. The glass has a refractive index of 1.556 at 515 nm (green) and 1.541 at 633 nm (red). This dispersion will result in the two colours being split as it exits the prism. What will be the angle between these two rays? Give you solution in degrees to 3 d.p. Part B) A pair of binoculars has been treated with an anti-reflection coating designed to work best at 500 nm. The coating is made of a material with a refractive index of 5.98 at this wavelength. What is the minimum thickness the coating could be? Give your solution in nm to 3 s.f.