Bragg's Law | Physics

Suppose, and X-ray bean is incident on a solid, making an angle θ with the planes of the atoms. These X-rays are diffracted by different atoms and the diffracted rays interfere. In certain directions, the interference is constructive and we obtain strong reflected X-rays. The analysis shows that there will be a strong reflected X-ray beam only if
2dsinθ=nλ
where n is an integer. this equation is known as Bragg's law.
Example: X-rays are known to be electromagnetic radiation with wavelength of the order of 1A
∘
. They are produced when accelerated electrons strike target inside an evacuated tube. It is well known that when an electron is accelerated through a potential difference of V it acquires energy eV. If all this energy is used in producing one quantum of X-radiation, then hf=eV. It is likely that the electron may have lost some of its acquired energy before producing the quantum of radiation. The f gives the maximum possible frequency of X-radiation emitted and that corresponds to the short wavelength limit of the emitted spectrum. In general, therefore, X-ray spectra consist of a continuous spectrum upon which is superposed a line spectrum that is characteristic of the element used as target. For some time after the discovery of X-rays, there was considerable speculation about the nature of X-rays. Max Von Laue found, in 1912 that if X-rays are passed through a crystal they get diffracted. As Laue
patterns are difficult to interpret, Bragg worked out a simple equation that predicts the conditions under which diffracted X-rays beams from a crystal are possible. In its simplest form, Bragg's Law is given by λ=2dsinθ where d is the perpendicular distance between the planes contining atoms and θ is the glancing angle at which the X-rays fall on the crystal. λ is known, the distance may be found from experimental measurements. This is the basis for the field of X-ray crystallography in which the structure of crystals is determined by using X-rays. Find the photon is the order of energy associated with an x-ray.

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