Question

What is electromagnetic induction?

Answer 1

We need to understand the phenomenon of electromagnetic induction to explain and give a comprehensive definition for the electromagnetic induction. The Faraday’s law of electromagnetic induction can be explained for clarity.

Complete step-by-step solution:
The electromagnetic induction is a phenomenon in which an electric field or an electromotive force is induced or created in a conductor by the effect of a changing magnetic field in which the conductor is placed. The electromagnetic induction as the word suggests is inter dependent on both electric field and magnetic field.
According to the Faraday’s law of electromagnetic induction, any rate of change in the magnetic flux experienced by a conducting loop is induced by a electromotive force, which is mathematically given as –
$\varepsilon =-\dfrac{d\phi }{dt}$
Where, the negative sign is from the Lenz’s law which shows that the electromagnetic induction is a result of opposition of the conductor to the change of state in the potential, $\varepsilon$ is the induced emf and $\phi$ is the magnetic flux related to the conductor.
The magnetic flux of material is given as the scalar product of the magnetic field and the area of cross-section of the conductor as –

& \phi =B.A \\\ & \therefore \phi =BA\cos \theta \\\ \end{aligned}$$ Where, B is the magnetic field, A is the area of cross-section and $$\theta $$ is the angle between the magnetic field and the area. Any change in any of the above-mentioned quantities – magnetic field, area of cross-section or the angle between the two can induce the electromotive force required for a current flow depending on the resistance offered by the conductor. **This is the electromagnetic induction. This is the required solution.** **Note:** The electromagnetic induction can be achieved by changing the area of the loop or the conductor. We can bring a bar magnetic into a loop connected to a galvanometer which causes a magnetic field increase when brought in and causes an induced emf in the loop.