In Young’s double slit experiment with sodium vapour lamp of wavelength 589 nm and the slits 0.589 mm apart, the half angular width of the central maximum is

Options

(a) sin⁻¹ 0.01
(b) sin⁻¹ 0.0001
(c) sin⁻¹ 0.001
(d) sin⁻¹ 0.1

Correct Answer:

sin⁻¹ 0.001

Explanation:

sin θ = λ / d

= 589 × 10⁻⁹ / 0.589 × 10⁻³ = 10⁻³ = 1 / 1000 = 0.001

Therefore, θ = sin⁻¹ 0.001