Faraday's Experiments

The discovery and understanding of electromagnetic induction are based on a series of experiments performed by Faraday. We shall study some of these experiments.

Experiment : 1    

        As shown faraday took a ring of soft iron in his historic expriment. An insulated conducting coil was wound on one side of the ring and connected to a battry.  

On the oppositside of this coil,another conducting coil was wound and connected with a sensitive galvanometer. The coil connected to a battry acts like a solenoid. When electric current is passed through the coil(i.e. solenoid), it produces a magnetic field.

Galvanometer measures electric current passing through the other coil. As the ring is of the soft iron, the magnetic field linesproduced remain confined in the ring itself. Almost all magnetic field lines pass through the ring and hence through the inner part of second coil and form closer loops. In other words, the ring connects two coils through the magnetic field lines.

When faraday passed a steady electric current through the left coil,no effect was observed in the galvanometer.During minute observations of every moment, he observed that the galvanometer shows a momentary deflection whenever the battry is switched on or off. In both the cases, the deflections of galvanometer were in opposite directions.

From his observation that galvanometer showed no deflection when a steady current is passed Faraday concluded that the steady current is not important but change of current plays an important role in this experiment.