Physics (AS & A Level) · May / June 2023 · Paper 13 · Question 29

A parallel beam of light of wavelength 600 nm is incident normally on a diffraction grating. The distance between adjacent slits in the grating is 2.0 × 10⁻⁶ m. A screen is placed parallel to the grating, at a distance of 1.50 m from the grating. Third-order diffraction maxima are observed at the two ends of the screen, as shown. What is the distance between the two ends of the screen?

1. A1.4 m
2. B2.7 m
3. C3.1 m
4. D6.2 m

As printed in the paper