1. What is the spacing d between the slits in a grating that has 300 lines/mm? 2. The spacing d is quite small, so this means that the angle 0 is generally not small and the small angle approximation is not valid. If the distance between the grating and the screen where the interference pattern is recorded is L, what will be the distance on the screen between adjacent bright fringes (in terms of d, 1, and [)?\fBeetles of the subfamily Sphaeridiinae have a set of parallel ridges on their cuticles that are spaced a few micrometers apart, and thus act as a diffraction grating for visible light. The figure below shows an electron micrograph of the cuticle of Sphaeridiinae gen. sp. (Hydrophilidae) as well as a photo of the beetle showing the diffraction of white light. (c) ONE 11.3 03 Tom Electron micrograph (b) and photo (c) of the cuticle of the beetle Sphaeridiinae gen. sp. (Hydrophilidae). The micrograph shows the ridges that form a diffraction grating, and the photo shows the resulting diffraction in zeroth order through third order.' In (b), the scale bar = 20 um. 1. Use a ruler to measure the spacing between the ridges shown in the electron micrograph (note the scale bar). Based on your measurement, what would be the difference between the angles (for the m = 1 bright fringes) at which red light (600 nm) and blue light (400 nm) would be deflected? 2. Try to calculate the angle for m = 3 for red light. Now take a look at the photo and see if you can find the m = 3 red spot (look below the line marked "3"). Explain how your calculation is consistent with the photo.a. What aspect of the structure of the DNA molecule causes the orientation of the pattern (the basic "X" shape)? b. What aspect of the structure of the DNA molecule causes the missing layer lines? 2. If you want to measure the difference in wavelength between light from two sources that have wavelengths that are very close together (Le. one has wavelength , and the other has wavelength , = 2, + Al and AX is much smaller than A ), would you want to use a diffraction grating with a small number of lines/ mm or a large number of lines/mm? Explain