 # GCSE Level Questions: Transformers Q8. The diagram shows the structure of a traditional transformer. (a) There is an alternating current in the primary coil of the transformer.

State what is produced in the iron core.

[2 marks]

(b) A transformer has only ten turns of wire on the secondary coil. If the potential difference across the secondary coil is 1.15 V and the potential difference across the primary coil is 230 V

Calculate the number of turns on the primary coil.

[3 marks]

(c) In most transformers, the power output is less than the power input. State why.

[1 mark]

(d) Two students investigated how magnets can be used to produce a potential difference.

The students held a coil of wire above a magnet. They quickly lowered the coil so that the magnet was inside the coil, as shown in the diagram. The students recorded the maximum potential difference for coils with different numbers of turns of wire. The results are shown below.

 Number of turns of wire in the coil Maximum potential difference / V Results from student 1 Results from student 2 5 0.09 0.08 10 0.20 0.15 15 0.31 0.25 20 0.39 0.33 25 0.51 0.39

(d)

(i) State the resolution of the voltmeter and give one reason why the resolution of the voltmeter is suitable for this investigation.

[2 marks]

(ii) The two students used exactly the same equipment to carry out their investigations. Both students recorded their results correctly. Give the reason why student 2 got different results from student 1.

[1 mark]

(iii) The students decided that even though the results were different, there was no need to repeat the investigation. How do the results show that the investigation is reproducible?

[1 mark]

(iv) State the name of the process which causes the potential difference to be produced in this investigation.

[1 mark]

(e) A transformer has been developed that can be used with many different devices.

Suggest one advantage of having a transformer that can be used with many different devices.

[1 mark]

(12 Marks Total)