Physics (AS & A Level) · Oct / Nov 2020 · Paper 13 · Question 30

Light of wavelength $5.30 \times 10^{-7}\,\mathrm{m}$ is incident normally on a diffraction grating. The first-order maximum is observed at an angle of $15.4^\circ$ to the direction of the incident light. What is the angle between the first-order and second-order diffraction maxima?

1. A$7.7^\circ$
2. B$15.4^\circ$
3. C$16.7^\circ$
4. D$32.1^\circ$

As printed in the paper