The fringes observed in a double-slit interference experiment when the two slits are illuminated by white light show dispersion of both light and color. The central maximum is white, but as we move away from the central mximum, the fringes become less distinct and more colorful.
(a) What is special about the central maximum that makes it white? Explain the presence of colors in the outlying fringes. Your answer should mention diffraction, both constructive and destructive interference, wavelength and path difference.
(b). Suupose that the slit widths are increased. What happens to the number of fringes and the spacing between fringes?
(c) Suppose that the distance between the slits is increased. What happens to the number of fringes and the spacing between the fringes? d. Suppose that the double-slit mask is replaced with a diffraction grating with 600 lines/millimeter. What happens to the brightness of the fringes and the width of the fringes? e. Suppose the diffraction grating in
(d) is illuminated with light of wavelength 500nm. A very wide viewing screen is 2.0 m behind the grating. What is the distance between the two m-1 fringes?
(e) how many bright fringes can be seen on the screen?