A crystal is irradiated with x-rays with a wavelength of 0.120 nm.The atomic planes in the crystal are separated by 0.21 nm.At what angles of incidence with respect to the normal will the x-rays reflect from the crystal?
A)73°,55°,31°
B)only 55°
C)only 73° and 31°
D)only 73°

Question

Quizplus · Accepted Answer

Using Bragg's Law, nλ = 2d sin(θ), where n is the order of reflection, λ is the wavelength, d is the distance between planes, and θ is the angle of incidence. For n=1, θ can be calculated for each angle, and 73°, 55°, and 31° satisfy the equation.

A Crystal Is Irradiated with X-Rays with a Wavelength of 0.120