Question

The angle of reflection for monochromatic X-rays from a crystal whose atomic spacing is 2.5 A° is 15°. calculate the wavelength of X-rays.

Answer 1

The wavelength of X-rays will be 1.294 A°

Explanation :

Given,

angle of reflection of x-rays , θ = 15°

atomic spacing of x-rays, d = 2.5 A° = 2.5 x 10⁻¹⁰ m

we know that,

2dsinθ = nλ

for n = 1

=> λ = 2dsinθ

=> λ = 2 x 2.5 x 10⁻¹⁰ x sin15°

=> λ = 2 x 2.5 x 10⁻¹⁰ x 0.2588

=> λ = 1.294 x 10⁻¹⁰ m = 1.294 A°

Hence the wavelength of X-rays will be 1.294 A°

I hope it helps.