In 1831 Michael Faraday reported on a series of experiments, including three tha
ID: 1539789 • Letter: I
Question
In 1831 Michael Faraday reported on a series of experiments, including three that (with some violence to history) can be characterized as follows: Experiment 1. He pulled a loop of wire to the right through a magnetic field (Fig. 7.21a). A current flow n the loop Experiment 2. He moved the magnet to the left, holding the loop still (Fig. 7.21b) Again, a current flowed in the loop. Experiment 3. With both the loop and the magnet at rest (Fig. 7.21c), he changed the strength of the field (he used an electromagnet, and varied the current in the coil). Once again, current flowed in the loopExplanation / Answer
The Faradays Law of electro magnetic induction is explained using the above three experiments
Faradays First Law
whenever there is relative motion between conductor and a magnetic field, the flux linkage with a coil changes and this change in flux induces a voltage across a coil. and the current flows through the loop.
Experiment 1. The magnet is stationary and the loop is moved (relative motion between conductor and a magnetic field) an emf is induced in the coil which drives the current through the loop/condcutor. (Faradays First Law)
Experiment2. Here the loop is stationary and the magnetci field is varied/changed by relative motion between two.
Hence the result is same of the first case with an induced emf in the coil.(Faradays First Law)
Expriment3 : Even though both magnet and coil are physically at rest ( No relative motion betweenn two). But ideal case the magnet means the magnetic field so the magnetic field is changed using the current, number of turns of coils in an electromagnets. The change in magnetic filed induces a change in the flux linkage with the coil. and emf is induced in the coil. ( Faradays second Law).
It states that the magnitude of emf induced in the coil is equal to the rate of change of flux that linkages with the coil.
summary of the experiment is that an emf can be induced in the coil whenever there is a relative motion of either the coil or magnet or the change in magnetic field/flux linkage.