Faraday’s experiments on electromagnetic induction.

 Faraday’s experiments are now used for electric power generation. Modern electric power generation is also used with the principles of Faraday's electromagnetic induction. Here there two experiments are used to understand electromagnetic induction.

                  

First experiment

Make a circuit set up consisting of a coil and a galvanometer. When a bar magnet is inserted into the stationary coil, with its north pole facing the coil, there is a momentary deflection in the galvanometer. This deflection indicates the induced current. 

If the bar magnet is kept stationary inside the coil, the galvanometer does not indicate deflection. Now the bar magnet is withdrawn from the coil, and the galvanometer again gives momentary deflection. So the electric current flows in the opposite direction. The bar magnet is reversed which means the South Pole faces the coil, the deflection is opposite to that in the case of the North Pole.

Second experiment

Make two closed circuits consisting of a coil, battery, and key, this is the primary circuit. The secondary circuit consists of a coil and galvanometer only. The two circuits are kept at rest concerning one another. 

If the primary circuit is closed, an electric current starts flowing in the primary circuit. At that time, the galvanometer gives a momentary deflection. After that electric current reaches a certain steady value, no deflection is observed in the galvanometer. 

Likewise, if the primary circuit is broken, the electric current starts decreasing and there is again a sudden deflection but in the opposite direction. From this experiment, we concluded that whenever the electric current in the primary circuit changes, the galvanometer shows deflection. Which means the induced current is produced by electromagnetic induction.

          The application of electromagnetic induction is everywhere in modern life. Like all home appliances and your mobile, all need electricity for their operation. Our life would not be possible without electricity and electricity would not be possible without the discovery of electromagnetic induction.

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