Definition of electromagnetic induction: Electromagnetic induction is most accurately described as the generation of which quantity from which cause?

Introduction / Context:
Electromagnetic induction is the backbone of electric power generation and many sensing technologies. Understanding the definition clarifies why rotating machinery, moving magnets, or time-varying fields can produce usable electrical power.

Given Data / Assumptions:

• We focus on the cause–effect relationship identified by Faraday’s law.
• “Electricity” here means induced voltage/current in a conductor.
• Magnetism refers to magnetic fields or changing magnetic flux.

Concept / Approach:
Faraday’s law states that a changing magnetic flux through a loop induces an electromotive force around the loop. Thus, motion of a conductor within a magnetic field or variation of the field over time generates an electrical response. This is succinctly “electricity from magnetism.”

Step-by-Step Solution:

Verification / Alternative check:
In generators, a coil rotates in a static magnetic field, changing flux → induced sinusoidal emf. In transformers, a time-varying primary current creates a changing flux in the core → induced voltage in the secondary (no mechanical motion required).

Why Other Options Are Wrong:

• Electricity from electricity: That is conduction or amplification, not induction.
• Magnetism from electricity: That is the inverse effect (Ampère's law), not induction.
• Magnetism from magnetism: Tautological and not a generation mechanism.

Common Pitfalls:
Confusing electromagnetic induction with electromagnetic radiation or with the magnetic field produced by a current (the latter is the opposite direction of causality).

Final Answer:
electricity from magnetism