You send coherent 550 nm light through a diffraction grating that has slits of equal widths and constant separation between adjacent slits. You expect to see the fourth-order interference maximum at an angle of 66.6 with respect to the normal to the grating. However, that order is missing because 66.6 is also the angle for the third diffraction minimum (as measured from the central diffraction maximum) for each slit. (a) Find the center-to-center distance between adjacent slits. (b) Find the number of slits per mm. (c) Find the width of each slit.

b) A Fabry-Perot device contains two parallel part-reflective surfaces, each with a power re- flection coefficient R = 0.92, separated by an air gap of 40 μm. The device is used at a small but non-zero angle of incidence, such that there is a transmission maximum at wavelength 589 nm. Calculate the coefficient of finesse, and the resolving power. If a sodium lamp emits 2 spectral lines at 589.0 and 589.6 nm respectively, comment on whether these two lines can be resolved by the device.

A hydrogen gas discharge lamp is used as a coherent light source illuminating NN slits in a barrier with a slit separation of 28 μmμm. The interference pattern is projected on a screen 2.00 m from the barrier. The first-order principal maxima to one side of the central maximum. The number of slits is sufficiently large that the individual lines are sharp and widely separated. Note that there are four different colors appearing in the source, violet is the color closest to the central maximum. λ=656λ=656 nm (red) λ=486λ=486 nm (cyan) λ=434λ=434 nm (blue-violet) λ=410λ=410 nm (violet) The blue-violet line is thin and somewhat faint, and it may be difficult to see without enlarging the figure. When viewing multiple orders of the interference pattern, the color sequence may change due to the interleaving of the different orders. 1. Using the values given in the problem statement, what is the distance along the screen, in centimeters, from the the central maximum to the first line?  2.…

The width of the central peak in a single-slit diffraction pattern is 5.0 mm. The wavelength of the light is 600. nm, and the screen is 1.9 m from the slit. (a.) What is the width of the slit in microns? (D= ?)  (b.) What is the ratio of the intensity at 4.2mm from the center of the pattern to the intensity at the center of the pattern? (I/I0= ?)