Question

Green light with a wavelength of 580nm goes through a pair of slits, travels at a 30° degree angle from the slits, and ends on a screen. The slits are 0.00001914 m apart. Will the fringe on the screen show constructive or destructive interference? (Tip: Don’t round any of the numbers while doing your calculations)

Answer 1

To obtain destructive interference for a double slit the path length difference must be a half-integral multiple of the wavelength, or

$$d \sinθ = (m + \frac{1}{2}) λ (1)$$

Using (1) we get:

m=16.5

Answer:

destructive interference