Question

A double slit separated by 0.0578 mm is placed 1.45 m from a screen.
(a) If yellow light of wavelength 585 nm strikes the double slit, what is the separation between the zeroth-order and first-order maxima on the screen? cm
(b) If blue light of wavelength 414 nm strikes the double slit, what is the separation between the second-order and fourth-order maxima?

Answer 1

Part A)

The formula for maxima for the double slit is

y = λLm/d   Between 0 and 1, m will equal 1, thus...

y = (585 X 10^-9)(1.45)/(5.78 X 10^-5)

y = .0147 m which is 1.47 cm

Part B) Between second and fourth order, m = 2

y = (414 X 10^-9)(1.45)(2)/(5.78 X 10^-5)

y = .0208 m   which is 2.08 cm