Magnetism and the Motor Effect | Edexcel GCSE Physics, Higher tier (1PH0)
Magnetism and the Motor Effect
- 96 questions
- 8 subtopics
- Paper 2
- Paper 2
Magnetism and the Motor Effect is examined in Paper 2, Physics 2.
It covers magnetic poles, permanent and induced magnets, uses of magnetic materials, the magnetic field around a bar magnet, plotting compasses and the Earth's magnetic field, the magnetic effect of an electric current, solenoids and electromagnets, the motor effect and Fleming's left-hand rule and the force on a conductor, and how a motor turns.
Sample questions from Magnetism and the Motor Effect
Answer each one closed book first, then open the answer.
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Magnetic poles, permanent and induced magnets
Explain why attraction to a magnet does not show that an iron nail has been magnetised.
Show the answer
An unmagnetised piece of iron is attracted to a magnet as well. -
Uses of magnetic materials
Explain why the core of an electromagnet is made of iron rather than steel.
Show the answer
Iron magnetises strongly and loses almost all its magnetism as soon as the current is switched off. -
The magnetic field around a bar magnet
State where the magnetic field of a bar magnet is strongest.
Show the answer
It is strongest at the poles. -
Plotting compasses and the Earth's magnetic field
Describe what a row of plotting compasses shows when they are placed on a bench far from any magnet.
Show the answer
They all settle pointing the same way, along the Earth's magnetic field. -
The magnetic effect of an electric current
State what happens to the magnetic field around a straight wire when the direction of the current is reversed.
Show the answer
The field lines circle the wire in the opposite direction. -
Solenoids and electromagnets
Explain why the magnetic field inside a solenoid is so strong.
Show the answer
Inside the coil the fields from all the separate turns point the same way, so they add together. -
The motor effect and Fleming's left-hand rule
Explain why a wire between the poles of a magnet feels no force when the current is switched off.
Show the answer
With no current the wire has no magnetic field of its own to interact with the magnet's field. -
The force on a conductor, and how a motor turns
A 0.12 m length of wire carrying a current of 3.0 A at right angles to a magnetic field feels a force of 0.72 N. Calculate the magnetic flux density.
Show the answer
Magnetic flux density = 0.72 ÷ (3.0 × 0.12) = 2.0 T.
The 8 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Magnetic poles, permanent and induced magnets | Attraction and repulsion between poles, proving that a bar is a magnet, the poles of a bar magnet, magnetic forces as non-contact forces, and permanent and induced magnets, including chains of paper clips and why induced magnetism always attracts. | 12 |
| Uses of magnetic materials | Iron, cobalt, nickel and steel as magnetic materials, why steel makes permanent magnets and iron makes electromagnet cores, temporary magnetic materials, and magnets in loudspeakers, alloys and scrapyard cranes. | 8 |
| The magnetic field around a bar magnet | What a magnetic field is, the direction and strength of the field lines around a bar magnet, the uniform field between opposite poles, and why field lines never cross. | 8 |
| Plotting compasses and the Earth's magnetic field | Mapping a field with a plotting compass, what the needle lines up with, evidence that the Earth has a magnetic field, the pole near geographic north, and the molten outer core. | 13 |
| The magnetic effect of an electric current | Showing that a current in a straight wire makes a field, its circular shape, the right-hand grip rule, reversing the current, and how current and distance set the field strength. | 12 |
| Solenoids and electromagnets | What a solenoid is, the strong uniform field inside it and the weak field outside, its bar-magnet field shape, strengthening an electromagnet with more current, more turns or an iron core, and reversing its poles. | 8 |
| The motor effect and Fleming's left-hand rule | The motor effect and the equal and opposite force on the magnet, how the angle to the field, the current and the field strength set the force, interacting fields, forces between parallel wires, and Fleming's left-hand rule. | 19 |
| The force on a conductor, and how a motor turns | Force = magnetic flux density × current × length, the tesla and what 1 T means, calculating force, flux density, current and length, and how a direct current motor turns, with its split-ring commutator, brushes and direction of rotation. | 16 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
Edexcel GCSE Physics, Higher tier Active Recall Guide
Every topic, not just this one. 2,063 questions with their answers.