ELM-010 · Magnetism and electromagnetic induction Sample material

Electromagnetic induction. Alternating current

Faraday's experiments, Lenz's law and the basic law of electromagnetic induction, self-induction, inductance and magnetic field energy; resistance, capacitance and inductance in AC circuits, phasor diagrams, power and effective (rms) values.

Estimated time: 3 h 6 activities

Learning objective

Explain electromagnetic induction, Faraday's law and Lenz's law.
Master the concepts of self-induction, inductance and magnetic field energy.
Study the behaviour of R, L and C elements in AC circuits and the phasor-diagram method.
Learn to calculate AC power, the power factor and effective (rms) values.

Expected outcomes

Can determine the induced EMF and the direction of the induced current when the magnetic flux changes.
Can calculate the inductance of a coil, the self-induced EMF and the magnetic field energy.
Can find the impedance, phase shift, current and resonant frequency of a series RLC circuit.
Can calculate active power, rms values and the transformer turns ratio.

Interactive modelElectromagnetic induction: a coil and a magnet
Interactive modelAC circuit: phasor diagram and resonance

Activities

Lecture
Lecture · 1 h 20 min · required
Solving problems on electromagnetic induction, self-induction, alternating current (R, L, C, power, rms values), electrical oscillations, resonance, displacement current and electromagnetic waves
Practice · 1 h 20 min · required
Verification of Ohm's law for alternating current
Laboratory · 1 h 20 min · optional
Determination of the efficiency of a transformer
Laboratory · 1 h 20 min · optional
Equations of the electromagnetic field
Self-study · 6 h · optional
Final test
Test · 20 min · required · pass ≥ 70%

Completion conditions

  • Lecture
  • Solving problems on electromagnetic induction, self-induction, alternating current (R, L, C, power, rms values), electrical oscillations, resonance, displacement current and electromagnetic waves
  • Final test — at least 70%