Question

A pair of slits, separated by 0.150 mm, are illuminated by light with a wavelength of 643 nm. An interference pattern is observed on a screen at 140 cm from the slits. Consider a point seen on the screen that is located 1.80 cm to the right of the central bright fringe. Will the point be a minimum (destructive) point, a maximum (constructive) point or somewhere in between

Answer 1

Answer:

Explanation:

slit separation d = .15 mm

screen distance D = 1.4 m

wavelength of light used λ= 643 x 10⁻⁹ m

position of n th bright fringe x

x = n x λ D / d

1.8 x 10⁻² = n x 643 x 10⁻⁹ x 1.4 / .15 x 10⁻³

1.8 x 10⁻² = n x 6 x 10⁻³

n = 3

So 3 rd bright fringe will be formed at a point 1.8 cm from the central bright fringe .