Question

A laser beam is incident on two slits with a separation of 0.195 mm, and a screen is placed 5.30 m from the slits. If the bright interference fringes on the screen are separated by 1.62 cm, what is the wavelength of the laser light

Answer 1

Answer:

596.038 nm

Explanation:

d = separation between the two slits = 0.195 mm = 0.195 x 10⁻³ m

D = screen distance = 5.30 m

λ = wavelength of laser light

w = distance between the bright fringes = 1.62 cm = 0.0162 m

Distance between the bright fringes is given as

$w = \frac{D\lambda }{d}$

$0.0162 = \frac{(5.30)\lambda }{0.195\times 10^{-3}}$

λ = 5.96038 x 10⁻⁷ m

λ = 596.038 x 10⁻⁹ m

λ = 596.038 nm