Question

Light from a sodium vapor lamp (λ-589 nm) forms an interference pattern on a screen 0.91 m from a pair of slits in a double-slit experiment. The bright fringes near the center of the pattern are 0.19 cm apart. Determine the separation between the slits. Assume the small-angle approximation is valid here.

Answer 1

separation between the slits is 0.28 mm

Step-by-step explanation:

given data

wave length λ = 589 nm = 589 ×
`10^(-9)` m

distance between slits and the screen D = 0.91 m

fringes weight y = 0.19 cm = 0.19 ×
`10^(-2)` m

solution

we find here the spacing between the two slits i.e d

so use here formula that is

y = λD ÷ d .........................1

put here value we get

0.19 ×
`10^(-2)` =
`(589*10^(-9)*0.91)/(d)`

solve we get

d = 0.28 mm