Question

A laser beam is incident on two slits with a separation of 0.220 mm, and a screen is placed 4.80 m from the slits. If the bright interference fringes on the screen are separated by 1.60 cm, what is the wavelength of the laser light

Answer 1

λ = 7.333 x 10⁻⁷ m = 733.3 nm

Step-by-step explanation:

We can use the formula of fringe spacing from Young's Double Slit Experiment, to find the wavelength of light:

Δx = λL/d

where,

Δx = fringe spacing = 1.6 cm = 0.016 m

λ = wavelength of laser light = ?

L = Distance between slits and screen = 4.8 m

d = slit separation = 0.22 mm = 0.00022 m

Therefore, using these values in the given equation, we get:

0.016 m = (λ)(4.8 m)/(0.00022 m)

λ = (0.016 m)(0.00022 m)/(4.8 m)

λ = 7.333 x 10⁻⁷ m = 733.3 nm