| P2.1 |
Properties of magnets:
- Know and be able to use the terms north pole, south pole, attraction and repulsion.
- Know the magnetic field pattern around a bar magnet (including direction).
- Understand the difference between soft and hard magnetic materials (e.g. iron and steel).
- Qualitatively understand induced magnetism.
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| P2.2 |
Magnetic field due to an electric current:
- Know and understand the magnetic effect of a current.
- Know the magnetic field patterns around current‑carrying wires (including direction) for straight wires and coils/solenoids.
- Know and understand the factors affecting magnetic field strength around a wire.
- Understand the difference between permanent magnets and electromagnets.
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| P2.3 |
The motor effect:
- Know that a wire carrying a current in a magnetic field can experience a force.
- Know the factors affecting the direction of a force on a wire in a magnetic field (including the left‑hand rule).
- Know the factors affecting the magnitude of the force on a wire in a magnetic field.
- Know and be able to apply $\mathrm{F=BIL}$ for a straight wire at right angles to a uniform magnetic field.
- Know and understand the construction and operation of a dc motor, including factors affecting the magnitude of the force produced.
- Understand applications of electromagnets.
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| P2.4 |
Electromagnetic induction:
- Know and understand that a voltage is induced when a wire cuts magnetic field lines, or when a magnetic field changes.
- Know the factors affecting the magnitude of an induced voltage.
- Know the factors affecting the direction of an induced voltage.
- Understand the operation of an ac generator, including factors affecting the output voltage.
- Interpret the graphical representation of the output voltage of a simple ac generator.
- Understand applications of electromagnetic induction.
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| P2.5 |
Transformers:
- Know and understand the terms step‑up transformer and step‑down transformer.
- Know and use the relationship between the number of turns on the primary and secondary coils, and the voltage ratio: $\mathrm{\frac{V_p}{V_s}=\frac{N_p}{N_s}}$
- Know that a consequence of $\mathrm{100\%}$ efficiency is total transfer of electrical power, and that this gives rise to the following relationship: $\mathrm{V_pI_p=V_sI_s}$. Know and use this relationship to solve problems.
- Understand power transmission, including calculating losses during transmission and the need for high voltage.
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