Pearson Edexcel International GCSE (9–1) · PHYSICS · Section
USING TRANSFORMERS TO CHANGE VOLTAGES
15 practice questions
Practice questions
11–15 of 15
Question 11
1 mark · Normal
Answer and see the solution →Which part of a transformer links the magnetic field between the two coils?
- A.Plastic casing
- B.Copper wires
- C.Soft iron core
- D.Steel rod
Question 12
4 marks · Normal
Answer and see the solution →A step-down transformer is used to supply 6 V to a device. The primary coil has 240 turns and the secondary coil has 40 turns. What is the input voltage supplied to the primary coil?
Question 13
3 marks · Normal
Answer and see the solution →The table shows data for four transformers. Complete the table by filling in the missing voltages using the transformer equation.
Primary voltage (V) Secondary voltage (V) Primary turns Secondary turns 15 300 600 9 450 150 6 80 40 Question 14
4 marks · Normal
Answer and see the solution →Figure 1 shows a transformer used to supply power to a small device.
Figure 1. Transformer structure. (a)[1 mark]Label the primary and secondary coils on Figure 1.
(b)[3 marks]Explain why the core is made from soft iron and not another material.
Question 15
4 marks · Normal
Answer and see the solution →The primary coil of a transformer is supplied with 230 V and there is a current of 0.1 A in the primary. If the secondary voltage is 23 V, and the transformer is 100% efficient, calculate the secondary current.