9478 / 2027

Chapter 18

Electromagnetic Induction

Choose an area normal and a circuit reference, then identify what changes the magnetic flux linkage.

Infer induction from controlled evidence, calculate mean and local rates of linkage change, and connect induced effects to useful energy transfers.

Flux and equal-turn linkage, experimental induction evidence, Faraday and Lenz laws, alternating generation, magnetic braking and iron-core transformers. For 9478 (2027).

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Choose a topic

  1. Flux through a coil

    Use perpendicular area and a chosen normal to distinguish signed flux from the total linkage of a coil.

  2. Evidence for induction

    Interpret controlled magnet-coil observations to infer induction, opposing direction and magnitude factors.

  3. Linkage changes and induced direction

    Use a signed linkage-time gradient, distinguish mean from instantaneous e.m.f. and apply Lenz's law to a stated change.

  4. Alternating generation

    Connect a rotating coil and complete slip-ring circuit to signed linkage, terminal voltage and mechanical input.

  5. Magnetic braking and energy

    Trace an entering loop's induced current and opposing force, then compare mechanical input with resistive heating.

  6. Transformer voltage and current

    Explain changing core flux and electrical isolation, apply ideal ratios and assess a separate real-loss account.