As per Faraday's laws of electromagnetic induction, an e.m.f is induced in a conductor whenever

Step 1: Analyze the question The question asks about the condition under which an e.m.f. is induced in a conductor, according to Faraday's laws.

Step 2: The concept Faraday's law states that the induced e.m.f. is directly proportional to the rate of change of magnetic flux linkage (or the rate at which the conductor cuts magnetic flux):

E = −N (ΔΦ / Δt)

An e.m.f. is induced only when there is a change in flux linkage. This happens when a conductor moves across the field lines (cuts the flux), or when the magnetic field around a stationary conductor changes.

Step 3: Check each option

• A. Lies parallel to the magnetic flux: The conductor moves along the field lines and cuts none of them, so there is no change in flux linkage and no e.m.f. ❌
• B. Lies in a magnetic field: A conductor that is merely sitting in a steady field has no changing flux, so no e.m.f. ❌
• C. Lies outside but close to a magnetic field: Nearness alone does nothing. Without a change in flux, nothing is induced. ❌
• D. Cuts magnetic flux: The conductor crosses the field lines, so the flux linking it changes, and an e.m.f. is induced. ✅

Step 4: Answer The correct option is D.

Tip: Remember the key word is change. No cutting or changing of flux means no induced e.m.f. For JAMB, whenever you see "static conductor in a steady field" or "parallel to field," the answer is "no e.m.f."