Draw on Fig. 4.1 the paths taken by the red light and the violet light between the left-hand side of the prism and the screen at point R and point V.
State how the speed of red light and the speed of violet light change as each one passes from air into the glass.
The screen shows five other colours between the red light at point R and the violet light at point V. State the names of those five colours and write them in the correct order from red to violet.
State how the frequency and the wavelength of the coloured light vary as you go from red light to violet light.
On Fig. 4.1, point P is located immediately beside point R. No light is seen at point P, but a detector at point P registers radiation arriving at the detector. State which part of the electromagnetic spectrum is detected at point P.