Hii Gurkamal Singh..It is a device that is used to accelerate positively charged particles (like protons, deutrons, alpha particles and certain other heavier positive ions) to desired very high energies(or, velocities). Invented by Ernest O. Lawrence in 1929-1930 at University of california, Berkeley.

Hope you got it. All the best.

There are many such devices which have taken Science to a higher level, cyclotron is one of them.

Cyclotron is a circular particle accelerator which utilises a magnetic field to bend charged particles into a circular path and electric field to accelerate them to high velocities. 

Principle :- When a positively charged particle moves with a definite periodic time again and again perpendicular to uniform magnetic field and is accelerated repeatedly by high frequency electric field,  traces a spiral path of increasing radius. The positively charged particle is accelerated to high speed and gains sufficient large amount of energy. 

Radius of circular path traced by positive ion is directly proportional to velocity of positive ion. 

There are some limitations of cyclotron too. For example cyclotron cannot accelerate electrons because it has a small mass hence it moves with very high speed. Therefore it cannot remain inphase with field. 

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