As per Faraday's laws of electromagnetic induction, an e.m.f is induced in a conductor whenever
Answer Details
According to Faraday's laws of electromagnetic induction, an electromotive force (e.m.f) is induced in a conductor whenever it **cuts magnetic flux**. This means that for an e.m.f to be induced, the conductor must move in such a way that it intersects the magnetic lines of force. It is the relative motion between the conductor and the magnetic field that leads to the change in magnetic flux, resulting in the induction of e.m.f.
Let's explore why this is the correct answer using reasoning:
When the conductor lies parallel to the magnetic flux: In this case, there is no motion or cutting of magnetic lines of force, leading to no change in magnetic flux through the conductor, and thus no e.m.f is induced.
When the conductor lies in a magnetic field: Simply being within a magnetic field without any motion or change to the field does not induce e.m.f. There must be a change in the flux linkage for induction to occur.
When the conductor lies outside but close to a magnetic field: Proximity alone without interaction doesn't change the magnetic flux linked with the conductor, thereby not inducing any e.m.f.
When the conductor cuts magnetic flux: This is the condition necessary for the induction of e.m.f. The number of magnetic field lines interacting with the conductor changes, leading to a change in flux linkage, and consequently, e.m.f is induced.
Therefore, the phenomenon where a conductor cuts magnetic flux is essential for electromagnetic induction as per Faraday's laws.