Main properties of X-rays may be summarised as under:
(i) Like visible light, X-rays consist of electro magnetic waves of very short wavelength(or of very high frequency) and show reflection, refraction, interference, diffraction and polarisation etc.
(ii) They are not deflected by electric and magnetic field.
(iii) They posses high penetrating power and can pass through many solids which are opaque to visible light. The transparency depends on the density of the material. Higher the density of the substance, the less transparent it is to the X-rays. For example,sheet of lead 1 cm thick can absorb X-rays whereas aluminium sheet of same thickness cannot.
The penetrating power of X-rays depends upon (a) the voltage applied across the cathode and anode of the X-ray tube and (b) the atomic number of the material of the cathode. Greater the accelerating potential of the X-ray tube and higher the atomic number of its target material, the more penetrating the X-rays produced.
(iv) They ionize a gas and also eject electrons from metals on which they fall.
(v) They cause fluorescence in many substances like barium, cadmium, tungstate and zinc sulphide etc.
(vi) They suffer compton scattering.
(vii) They have a destructive effect on living tissue. Exposure of human body of X-rays causes the reddening of skin and surface sores.
