An x-ray beam with wavelength 0.240 nmnm is directed at a crystal. As the angle of incidence increases, you observe the first strong interference maximum at an angle 66.0 ∘∘. What is the spacing ddd between the planes of the crystal?

Light from two different sources are incident upon the same side of a polarizing filter. light from one source is polarized with total intensity ip, while light from the other source is unpolarized with total intensity iu. as you rotate the polarizing filter through 360 degrees, the intensity of the transmitted light on the other side varies by a factor of 9. what is the relative intensity of the initial polarized source to the unpolarized source, or ip/iu?