Electromagnetic Induction

Question 1: Define Electromagnetic Induction.

Answer: 

Electromagnetic or magnetic induction is the production of an electromagnetic force around the electrical conductor in a changing magnetic field. 

Question 2: What are the applications of electromagnetic induction? 

Answer: 

Electromagnetic induction is essentially used for production of electricity. Electricity is generated by subjecting a metal to a changing magnetic field. This induces a current in the metal due to a force on the free electrons. 

• Dams use the energy of flowing water to drive coils of wire in a magnetic field to generate electricity. 
• Electromagnetic induction is also used for braking purpose in magnetic trains.
• Nuclear reactors generate heat, which is used to convert water to steam, that is used to drive turbines in a magnetic field. 

Question 3: What is the relationship between magnetic induction and current?

Answer:

We know that electric current can produce magnetic fields also support that magnetic field could produce electric currents. The production of electro motive force and currents by the changing magnetic field through a conducting loop is called magnetic induction. 

Question 4: State the difference between a magnetic field and an Electric field.

Answer: 

• The field of force present around a charged particle is known as electric field, while a magnetic field is a field of force around a magnet or around a conductor in which charged particle is present. 
• The electric field is expressed in Newtons per Coulomb, or Volts per meter, whereas a magnetic field strength is expressed in Gauss or Tesla. 
• The force of an electric field is proportional to the electric charge, while the magnetic field is proportional to the electric charge as well as the speed of the moving charge.

Related Resources

• Faraday’s Law
• Inductance
• Lenz’s Law

Electromagnetism is a combination of two different phenomena i.e. Electricity and magnetism. Electricity and magnetism are interrelated, when electric charges move through a conductor they produce magnetic fields. The converse of this is also possible, In 1830, Michael Faraday in England and Joseph Henry in the USA conducted an experiment and demonstrated effectively that electric currents were induced in closed coils when placed in a changing magnetic field. 

The phenomenon in which electric current is generated by varying magnetic fields is appropriately called electromagnetic induction.

When an electric current is produced in a closed conducting loop when the flux of the magnetic field through the surface enclosed by this loop changes. This phenomenon is called electromagnetic induction, and the current produced an induced current. Electromagnetic induction is also called magnetic induction, as the principle is the same whether the process is carried out through electromagnetic or static magnets. 

Michael Faraday, in the year 1830 discovered electromagnetic induction and demonstrated it with a copper coil around a toroidal piece of iron, a galvanometer (a gauge-based device used to show currently), and a magnet. When the magnet was moved towards the coil, an EMF is created, and moved the gauge on the galvanometer was. If the north end of the magnet is drawn closer, the current flows one way and if the south end of the magnet is drawn closer, then the current flow in the opposite direction. This discovery of electromagnetic induction was a fundamental principle in understanding and harnessing electricity. 

The principle of electromagnetic induction is required in electronic components such as inductors and transformers. Electromagnetic induction is the basis of all types of electric generators and motors.