How does X-ray Tube Work?

X-ray tube works as follows:

1.The heated filament is positively charged and the tungsten target is negative.

2.Electrons are emitted from the heated filament towards the tungsten target due to the very high potential difference between them.

3.The tungsten target absorbs the electrons and releases some of the energy in the form of X-rays.

This process is very inefficient however and a lot of energy is released in heat. For this reason the tungsten target has a copper mounting because it conducts heat and is cooled with by circulating oil through the mount. Spinning  tungsten target at high speed also helps to stop it overheating.