X-Rays in Physics.
X-Rays are Electromagnetic Radiations having wavelength from a fraction of an Angstrom to about 100 Å.
They were discovered by Roentgen during his studies on the electrical discharge phenomena in gases – he found that an unknown radiation was produced when electrons collided with the walls of the tubes.
Properties of X-Rays
- They ionize the material through which they pass.
- They affect photographic plates in the same manner as visible light
- They cause fluorescence in certain chemical compounds like zinc sulphide
- They penetrate matter and are absorbed as they pass through it.
For the production of X-Rays, it is essential to keep high order vacuum in the tube so that the electrons emitted by the filament do not collide with the gas atoms before they reach the target.
Because if the electrons strike the atoms of the gas they will lose their energy by ionizing the gas, and the positive ions so produced will be attracted towards the filament and damage it by collision.
When some information is required about patient’s stomach by X-Rays, then the patient is administered some heavy – atom substance (like barium sulphate solution).
Heavy atoms diffract X-Rays sufficiently. So, those parts of the stomach where this solution goes are photographed on the plate.
This enables direction of some stone etc, in those parts.
The parts, where this solution does not reach, are not clearly photographed.
This shows that there is some obstruction in the path of the solution.
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