A student is investigating monochromatic light passing through a diffraction grating. A series of maxima are produced on a screen, as shown in Fig. 2.1. [Figure 2.1] The student measures the distance s between the central maximum and the second order maximum on the screen. The experiment is repeated for different wavelengths of light. It is suggested that s and the wavelength λ are related by the equation s² / (s² + D²) = 4N²λ² where D is the distance between the diffraction grating and the screen and N is the number of lines per unit length of the diffraction grating.