Chapter 21, Problem 39P

(λvacuum =640nm) red light (λ vacuum = 640 nm) and green light perpendicularly on a soap film (n=1.31) A mixture of (a vacuum = 512 nm) shines that has air on both side. What is the minimum nonzero thickness of the film, so that destructive interference to look red in reflected light? nm Causes it

Suppose the inteference pattern shown in the figure below is produced by monochromatic light passing through a diffraction grating, that has 260 lines/mm, and onto a screen 1.40m away. What is the wavelength of light if the distance between the dashed lines is 180cm? nm

How many (whole) dark fringes will produced on on an infinitely large screen if red light (2)=700 nm) is incident on two slits that are 20.0 μm apart?