The process of producing electric current by a changing magnetic field is referred to as

Step 1: Analyze the question The question asks for the name of the process in which a changing magnetic field produces an electric current.

Step 2: Explain the concept When the magnetic flux through a conductor or coil changes, an e.m.f. is induced in it. If the circuit is closed, a current flows. This is called electromagnetic induction, discovered by Michael Faraday.

• Faraday's law: the induced e.m.f. is proportional to the rate of change of magnetic flux linkage: E = −N(ΔΦ/Δt)
• Lenz's law: the induced current flows in a direction that opposes the change producing it (this is the meaning of the negative sign).

This is the principle behind generators, transformers and induction coils.

Step 3: Check each option

• A. Magnet induction: not a standard physics term.
• B. Electromagnetic induction: correct. A changing magnetic field produces an e.m.f. and current.
• C. Flux linkage: this is a quantity (N × Φ), not a process.
• D. Electrostatic induction: this is the redistribution of charge on a conductor by a nearby charged body. It involves electric charges, not a changing magnetic field.

Step 4: Answer The correct option is B. electromagnetic induction.

Exam tip: Match the keywords. "Changing magnetic field → current" means electromagnetic induction. "Charged body → charge separation" means electrostatic induction. Also remember that flux linkage is something you calculate, not a process.