physicus of x ray

x-ray

Definition
X rays are a type of radiation used in imaging and therapy that uses short wavelength energy beams capable of penetrating most substances except heavy metals
Electromagnetic radiation of wavelengths ranging between 5.0 × 10?6 and 5.0 × 10?4 ?m
X-rays are produced when fast-moving electrons with sufficient energy strike a target. Most of the electron energy is converted to heat, but a very minute amount —less than 1 per cent —is converted to x-rays
Spectrum of Electromagnetic Radiations. X-rays resemble visible light rays very closely but have the distinguishing feature that their wave lengths are very short
Feature of x-ray :
• No mass
• No charge
• Travel at the speed of light
• Short wave length
• High energy
• Source of x-ray from the electron shells
x-ray production :
• X-rays are generated by an x-ray tube, a vacuum tube that uses a high voltage to accelerate electrons released by a hot cathode to a high velocity. The high velocity electrons collide with a metal target, the anode, creating the x-rays. In medical x-ray tubes the target is usually tungsten



the insert is evacuated from air because :
• Prevent oxidation of the cathode filament
• Decrease resistance against electron movement
Advantage of oil in x-ray tube :
• Shock absorber
• Heat absorber