Physics (AS & A Level) · Oct / Nov 2024 · Paper 11 · Question 30

Light of wavelength λ is incident normally on a diffraction grating with a total number of N lines in width w. A second order maximum is observed at an angle of diffraction θ. What is N?

1. A\frac{w\lambda}{\sin\theta}
2. B\frac{2w\lambda}{\sin\theta}
3. C\frac{w\sin\theta}{2\lambda}
4. D\frac{w\sin\theta}{\lambda}

As printed in the paper