Electromagnetic induction: IGCSE Physics questions with answers
Free Electromagnetic induction questions for IGCSE Physics (0625), part of Electricity & magnetism. Each question has the answer and the marking points an examiner would look for.
A bar magnet is dropped through a coil of wire connected to a sensitive voltmeter. The magnet falls completely through the coil. 1 The induced e.m.f. is the same whichever pole of the magnet enters the coil first. 2 The induced e.m.f. would be the same if the magnet were dropped from a greater height. 3 Using a coil with more turns would increase the induced e.m.f. Which statements are correct?
A 1 and 3 only
B 2 and 3 only
C 1 only
D 3 only
Show answer
Answer: D
Question 2Multiple choice · 1 mark
Which change would NOT increase the e.m.f. induced when a magnet moves into a coil?
A using a coil of thicker wire with the same number of turns
B using more turns
C using a stronger magnet
D moving the magnet faster
Show answer
Answer: A
Question 3Structured · 4 marksA* challenge
A simple a.c. generator consists of a coil rotating between the poles of a magnet.
(a)
Explain why the output of the generator is alternating.
[2]
(b)
State the effect on the output of rotating the coil faster.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
sides of coil reverse direction of motion every half turn
each side of the coil moves up and then down through the field B1 so the induced e.m.f. reverses every half turn B1
2
(b)
larger peak e.m.f.; higher frequency
the peak voltage increases B1 the frequency increases B1
2
Question 4Structured · 10 marks
This question is about electromagnetic induction. A bar magnet is moved into and out of a coil connected to a sensitive ammeter.
(a)
Describe what the ammeter shows when the magnet is pushed in, held still and pulled out.
[3]
(b)
State two ways of increasing the induced e.m.f.
[2]
(c)
Explain why an e.m.f. is induced only while the magnet is moving.
[1]
(d)
The induced current produces a magnetic field. State the direction of the pole at the end of the coil as the north pole of the magnet approaches, and explain why.
[2]
(e)
In an a.c. generator, the coil rotates in a magnetic field. Explain why the output is alternating.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
deflects one way; zero; deflects the other way
in: needle deflects B1 held still: no reading B1 out: deflects in the opposite direction B1
3
(b)
move magnet faster; stronger magnet; more turns
Any 2 of: move the magnet faster; use a stronger magnet; more turns on the coil B2
2
(c)
field lines must be cut / magnetic field must change
e.m.f. is induced only when the magnetic field through the coil changes / field lines are cut B1
1
(d)
north pole; opposes the motion (energy conservation)
north pole (repels the magnet) B1 the induced current opposes the change producing it, otherwise energy would be created B1
2
(e)
each side moves up then down through the field; current reverses every half turn
each side of the coil moves up and then down through the field B1 so the direction of the induced e.m.f. reverses every half turn B1
2
Question 5Structured · 5 marks
A magnet is pushed into a coil connected to a sensitive ammeter. The ammeter needle moves.
(a)
Explain why a current is induced.
[2]
(b)
State two ways of increasing the size of the induced current.
[2]
(c)
State what happens to the needle when the magnet is pulled out.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
changing magnetic field cuts coil
the magnetic field in the coil changes (field lines are cut) B1 an e.m.f. is induced, which causes a current B1
2
(b)
faster; stronger magnet; more turns
Any 2 of: move the magnet faster; use a stronger magnet; use more turns on the coil B2
2
(c)
deflects the opposite way
it deflects in the opposite direction B1
1
Question 6Structured · 4 marks
A wire is moved down between the poles of a magnet. A voltmeter connected to the wire shows a reading.
(a)
Explain why there is a reading.
[2]
(b)
State the reading when the wire is held stationary.
[1]
(c)
State the effect of moving the wire upwards.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
wire cuts field lines; e.m.f. induced
the wire cuts magnetic field lines B1 an e.m.f. is induced across it B1
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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in