What is Plasma in Physics

In physics, to put the definition very simply, plasma is a fourth state of matter that comes after solid, liquid and gases. The state of plasma is achieved when gas or gases are heated to the extent that the atoms of the gas lose all electors. The resultant quasi-gas is a collection of nuclei and electrons that are free. The nuclei which has lost all the electrons are deemed to be ions, that is, they are electrically charged, to a substantial extent. The entire collection is thus, electrically charged and conductive. The basic process that takes place in formation of plasma is quite simple. When heated, energy gets pumped into the gas. This causes that gas to disassociate itself from its molecules and take the form of atoms, which further loose their negatively charged electrons. The atoms themselves retain positive charge and are thus, deemed to be positive ions. 

Plasma, thus, cannot occur naturally, i.e, in free environment on earth. It needs a controlled environment of electromagnetic field to survive without reacting. Stars, which are existent in space, are the best example of plasma. The vacuum of space prevents them from reacting. Scientists have laid down certain parameters that define plasma. These parameters include, the approximation of ions and electrons, the frequency and volume of iterations, size, lifetime, density, temperature and magnetic fields are the constituents of the definition.

The question 'what is plasma used for', is quite evident. The naturally existing plasma is in stars or lightning. Artificially produced plasma is included in applications such as neon signs and plasma display television. Coincidentally, Irving Langmuir in 1928, named the phenomenon, 'plasma' owing to the fact that it strongly resembled blood plasma. For more leads on plasma as a substance, you may have a look at some of its applications and how they work: