96.1k views
0 votes
Light with a wavelength of 560.0 nm is incident on a pair of slits with a separation of 0.380 mm. (a) Find the angles corresponding to the locations of the first three orders of bright fringes away from the central bright fringe

1 Answer

2 votes

Answer:

Angles corresponding to the locations of the first three orders of bright fringes away from the central bright fringe are;

∅₁ = 0.8439°

∅₂ = 0.1688°

∅₃ = 0.2533°

Step-by-step explanation:

Given that;

wavelength λ = 560 nm = 560 × 10⁻⁹

Separation between slits d = 0.380 mm = 0.00038

n = first three orders = 1st order, 2nd order and 3rd oder.

we know that for constructive interference;

λn = dsin∅

sin∅ = λn/d

∅ = sin⁻¹ ( λn/d )

where λ is wavelength, ∅ is the angle, d is the distance between slits, n is the order of constructive interference.

now;

-First order; n = 1

∅₁ = sin⁻¹(λn/d) = sin⁻¹( (560 × 10⁻⁹)×(1) /0.00038 )

∅₁ = sin⁻¹( 0.001473) = 0.8439°

-2nd order; n = 2

∅₂ = sin⁻¹(λn/d) = sin⁻¹( (560 × 10⁻⁹)×(2) /0.00038 ) =

∅₂ = sin⁻¹( 0.002947) = 0.1688°

-3rd order; n = 3

∅₃ = sin⁻¹(λn/d) = sin⁻¹( (560 × 10⁻⁹)×(3) /0.00038 ) =

∅₃ = sin⁻¹( 0.004421) = 0.2533°

Therefore, angles corresponding to the locations of the first three orders of bright fringes away from the central bright fringe are;

∅₁ = 0.8439°

∅₂ = 0.1688°

∅₃ = 0.2533°

User Dhamibirendra
by
3.5k points