Question

In a Young's double-slit experiment the wavelength of light used is 462 nm (in vacuum), and the separation between the slits is 2.1 × 10^-6 m. Determine the angle that locates (a) the dark fringe for which m = 0, (b) the bright fringe for which m = 1, (c) the dark fringe for which m = 1, and (d) the bright fringe for which m = 2.

Answer 1

Given

The condition of m^th order bright fringe is

The condition of m^th order dark fringe is

(a)

For m=0 dark fringe, put m=0, , into equation (2)

(b)

For m=1 bright fringe, put m=1, , into equation (1)

(c)

For m=1 dark fringe, put m=1, , into equation (2)

(d)

For m=2 bright fringe, put m=2, , into equation (1)