Answer a,b,c,d pls thank you!!

Grating Equation a. In one test experiment, an old monochromator was used. The graduate student wanted to figure out the line spacing of the grating. She used an intense HeNe laser (632.8nm), directed the beam into the entrance slit and observed the light emerging from the exit slit. She was able to manually change the angle of incidence. She observed red light exiting from the monochromator at three angles of incidence: 20, 43.8, and 73.9 ordered in decreasing intensity. Using your knowledge of diffraction and the grating equation explain the observation for each angle. b. Show by calculation and schematically(using the figures below) all the angles where constructive interference occurs for 1=600,2=400nm when illuminating the grating at a fixed angle of incidence (70). The grating has a line density of 1000 lines /mm. c. The FTIR has replaced spectrometers that use dispersal optics. For IR spectroscopy, calculate the line density of a grating (ie lines /mm ) that is needed to disperse IR radiation. Assume a 45 angle of incidence. Demonstrate your choice is correct by calculating the angles for first order diffraction for 1000 and 4000cm1. Show the angles on the grating below. d. With your choice of lines /mm, draw all the angles at which 1500cm1 would be constructively interfered using the same angle of incidence as in part c above