Physics (AS & A Level) · May / June 2024 · Paper 12 · Question 26

A diffraction grating with N lines per metre is used to diffract light of various wavelengths λ. The graph shows the relation between the diffraction angle θ and λ for different wavelengths in the nth order interference pattern. [graph of sin θ against λ] What is the gradient of the graph?

1. ANn
2. BN/n
3. Cn/N
4. D1/(Nn)

As printed in the paper