Question

Two slits are separated by 0.34 mm and are used to perform a double-slit experiment with a screen 1.6 m away from the slits. If the distance between a dark region and the nearest bright spot on the screen is 1.6 mm, what is the wavelength? Need Help? Talk to a Tutor

Answer 1

The expression for the wavelength is d sin theta = m lambda d(y/L) = m lambda lambda = dy/mL here d is the separation between the slit h is the spacing between the central fringe and the next fringe and D is the distance of the screen from the slits substitute 1.6 m fro L 1.6 mm for y and 1.6 mm for d lambda = dy/mL = (0.34 times 10^-3) (1.6 times 106-3)/(0.5) (1.6) = 0.68 times 10^-6 m