X ray are produced in Coolidge tube It consists of a thick
Last updated: 6/24/2023
X ray are produced in Coolidge tube It consists of a thick glass bulb evacuated to about 10 cm of Hg so that no discharge can pass in it A cathode serves as source of electron is made up of tungsten filament heated by a low voltage current A cylindrical metal shield S surrounds the filament and S kept at negative potential with respect to the filament is focuses the electron emitted form the filament on the target T The target is mounted on the surface of a copper block fixed to the end of a copper rod The rod is fitted with fins for air cooling or cooled by circulating water A potential difference of about 20 000 V is applied across the tube to accelerate the electrons The accelerated electrons strike to the target and produces continuous and characteristic x rays 3 In the Coolidge tube experiment Platinum is used as target material for the emission of k series x ray The K L and M energy level of this element are 7 8 x 10 eV 1 2 x 10 eV and 3 x 10 eV respectively C 3 x 10 m s 1 eV 1 6 10 9 and h 6 23 10 4 J s The wavelength of ka lines will be A 0 188 A B 0 376 C 0 999 A D 0 25A