IGCSE Physics Edexcel 4PH1

know that a voltage is induced in a conductor or a coil when it moves through a magnetic field or when a magnetic field changes through it and describe the factors that affect the size of the induced voltage

describe the generation of electricity by the rotation of a magnet within a coil of wire and of a coil of wire within a magnetic field, and describe the factors that affect the size of the induced voltage

describe the structure of a transformer, and understand that a transformer changes the size of an alternating voltage by having different numbers of turns on the input and output sides

explain the use of step-up and step-down transformers in the large-scale generation and transmission of electrical energy

know and use the relationship between input (primary) and output (secondary) voltages and the turns ratio for a transformer:

$\dfrac{\text{input (primary) voltage}}{\text{output (secondary) voltage}} = \dfrac{\text{primary turns}}{\text{secondary turns}}$

know and use the relationship:

input power = output power

$V_pI_p = V_sI_s$

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