An experimental physicist wants to calibrate an unmarked diffraction grating using a high-precision optical spectrometer and a sodium discharge lamp of known wavelength λ=5.89×10−7 m\lambda = 5.89 \times 10^{-7}\text{ m}λ=5.89×10−7 m (589 nm589\text{ nm}589 nm).
Describe an experimental procedure to determine the slit spacing ddd and the number of lines per millimetre NNN of this grating using the spectrometer.
In your description, explain how to:
