An x-ray beam with wavelength 0.240 nm is directed at a crystal. as the angle of incidence increases, you observe the first strong interference maximum at an angle 24.5 ∘. what is the spacing d between the planes of the crystal?

Which statement best describes the superposition principle? a.) if two in-phase waves arrive simultaneously at a point, their amplitudes add up b.) if two out-of-phase waves arrive simultaneously at a point, their amplitudes add up c.) if two in-phase waves arrive at a point one after another, their amplitudes add up d.) if two out-of-phase waves arrive at a point one after another, their amplitudes adds up