German physicist W. C. Rontgen (18451923) discovered X-rays in 1895 while studying cathode rays (which is a stream of electrons emitted by the cathode in a vacuum tube).
X-rays are also called Rontgen rays.
X-rays are produced when cathode rays are suddenly stopped by an obstacle.
Properties
1) They are high energy EM waves.
2) They are not deflected by electric and magnetic fields.
3) X-rays ionize the gases through which they pass.
4) They have high penetrating power.
5) Their over dose can kill living plant and animal overdose tissues and hence are harmful.
Uses
1) Useful in the study of the structure of crystals.
2) X-ray photographs are useful to detect bone fracture. X-rays have many other medical uses such as CT scan.
3) X-rays are used to detect flaws or cracks in metals.
4) These are used for detection of explosives, opium etc.