Question

Problem 22.05 Part A In a double slit experiment, if the separation between the two slits is 0.050 mm and the distance from the slits to a screen is 2.5 m, find the spacing between the first-order and second-order bright fringes when coherent light of wavelength 600 nm illuminates the slits.

A. 9.0 cm
B. 6.0 cm
C. 1.5 cm
D. 4.5 cm
E. 3.0 cm

Answer 1

Answer:

$x_1-x_2=3cm$

Explanation:

Two slits with separation, d, and distance from the slits to a screen, L, produce bright fringes. The spacing, x, between the central fringe and the n-order bright fringe.

$x=\lambda*n*L/d$

The spacing between the first and second bright is:

$x_1-x_2=(n_2-n_1)*\lambda*L/d=(2-1)*600 *10^{-9}m*2.5 m/(0.050*10^{-3}m)=0.03m=3cm$