THE TRANSFORMER
3 marks · EasyLook at the diagram of a transformer below and answer the questions.
Name the part labelled 'core' in the diagram and state its purpose in the transformer.
Is this transformer a step-up or a step-down transformer? Explain your answer.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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(a) Soft iron core. Its purpose is to provide a path for the magnetic field and link the coils efficiently.
(b) Step-down transformer, because the secondary coil (75 turns) has fewer turns than the primary coil (150 turns).
Common mistakes: Naming core as steel or copper; Confusing step-up and step-down
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Names the core as 'soft iron core'.
B2 (a) · 1 mark · States that its purpose is to link the two coils by providing a path for the magnetic field.
B3 (b) · 1 mark · Correctly identifies as step-down and gives correct reason (secondary coil has fewer turns than primary).
Worked solution
a) The core is a soft iron core. It links the magnetic field between the primary and secondary coils, allowing efficient transformer operation.
b) This is a step-down transformer because the secondary coil (75 turns) has fewer turns than the primary coil (150 turns).