Explain the principle and working of a cyclotron with a well labelled diagram.

What are its two uses?

Cyclotron

• It is used to accelerate charged particles or ions to high energy.

• Electric and magnetic field are used in combination to increase the energy.

• The working of a cyclotron is based on the fact that the frequency of revolution of charged particle is not dependent on the energy.

• Particle moves inside the two semi-circular disc-like metal containers D₁ and D₂ called Dees.

• When the particle moves from one Dee to another, it is acted upon by electric field.

• Electric field changes sign alternately. Therefore, the particle is accelerated by the electric field, which increases the energy of the particle.

• The increase in energy increases the radius of the circular path.

Hence, the path is a spiral one.

• Time period of revolution is

This frequency is called the cyclotron frequency.

• When the frequency of applied voltage is equal to cyclotron frequency, it is called resonance condition.

• Since radius of trajectory,

Hence, the kinetic energy of ions is .

uses of cylclotron

• it is used to bombard nuclei by accelerating particles and then study the nuclear reactions.
• it is used to produce radioactive substances in hospitals to give medical treatment
• to implant ions in solids to modify their properties and to synthesize new compounds