Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter
Electromagnetic Induction
61 practice questions
Topics covered
Practice questions
11–20 of 61
Question 11
3 marks · Normal
Answer and see the solution →A generator in a power station uses coils of wire and a rotating magnet. Explain how this generator produces electricity. State TWO factors that affect the size of the voltage it produces.
Question 12
4 marks · Normal
Answer and see the solution →A small dynamo attached to a bicycle wheel generates electricity for the bike’s lights. The speed of the bicycle and the voltage output were recorded:
Speed (m/s) Voltage (V) 2.0 0.5 3.0 0.9 4.0 1.2 5.0 1.5 (a)[1 mark]Describe the trend shown by the data.
(b)[1 mark]If the cyclist increases her speed from 2.0 m/s to 5.0 m/s, by what factor does the voltage across the dynamo increase?
(c)[2 marks]Explain why increasing the speed of the bicycle causes the voltage to increase.
Question 13
4 marks · Normal
Answer and see the solution →A simple generator consists of a coil of wire rotating between the poles of a magnet.
(a)[2 marks]Draw a labelled diagram showing a coil rotating between two magnets.
(b)[2 marks]Describe what would happen to the induced voltage if the coil is rotated faster.
Question 14
3 marks · Normal
Answer and see the solution →Describe an experiment you could do to show how a voltage is induced in a coil when a magnet moves nearby.
(a)[1 mark]Name the apparatus you would use.
(b)[2 marks]Describe how you would carry out the experiment and what you would observe on the measuring instrument.
Question 15
1 mark · Normal
Answer and check →Which of these changes would NOT increase the voltage induced in a coil when a magnet moves nearby?
- A.Using more turns of wire in the coil
- B.Moving the magnet more slowly
- C.Using a stronger magnet
- D.Pushing the magnet in and out more rapidly
Question 16
1 mark · Easy
Answer and check →Which part of a transformer is responsible for linking the magnetic field between the primary and secondary coils?
- A.Soft iron core
- B.Plastic casing
- C.Copper insulation
- D.Aluminium case
Question 17
1 mark · Easy
Answer and see the solution →State whether a transformer can be used with direct current (d.c.).
Question 18
1 mark · Easy
Answer and see the solution →What is the function of a step-up transformer?
Question 19
3 marks · Easy
Answer and see the solution →A transformer has 200 turns on its primary coil and 800 turns on its secondary coil.
(a)[1 mark]State whether this is a step-up or step-down transformer.
(b)[2 marks]If the voltage across the primary coil is 5 V, calculate the voltage across the secondary coil.
Question 20
3 marks · Easy
Answer and see the solution →A step-down transformer has 900 turns on its primary coil and 90 turns on its secondary coil. The primary voltage is 225 V.
(a)[2 marks]Calculate the secondary voltage.
(b)[1 mark]State one use for a step-down transformer.