When an x-ray beam is scattered off the planes of a crystal, the scattered beam creates an interference pattern. This phenomenon is called Bragg scattering. For an observer to measure an interference maximum, two conditions have to be satisfied
An x-ray beam with wavelength 0.200nm is directed at a crystal. As the angle of incidence increases, you observe the first strong interference maximum at an angle 28.0°. What is the spacing d between the planes of the crystal?
Find the angle at which you will find a second maximum.
Will you observe a third maximum?
You have been asked to measure the width of a slit in a piece of paper. You mount the paper 80.0 centimeters from a screen and illuminate it from behind with laser light of wavelength 633 nanometers (in air). You mark two of the intensity minima as shown in the figure, and measure the distance between them to be 17.9 millimeters.
What is the width α of the slit?
If the entire apparatus were submerged in water, would the width of the central peak change?