A manufacturer uses a long solenoid to test magnetic field sensors. A constant current flows through the solenoid.
A magnetic field probe is placed at four positions. A larger probe reading indicates a stronger magnetic field.
| Position | Location of probe | Probe reading in mT |
|---|---|---|
| P | Inside, one-quarter of the way along the solenoid | 3.7 |
| Q | Inside, halfway along the solenoid | 3.8 |
| R | Inside, three-quarters of the way along the solenoid | 3.7 |
| S | Outside, beside the midpoint of the solenoid | 0.60 |
Using the data, describe the magnetic field inside the solenoid and how it compares with the field outside the solenoid.
Give the reason why winding a current-carrying wire into a solenoid produces a stronger magnetic field than the straight wire would.
90 exam-style questions on AQA GCSE Physics 7.2 The motor effect, covering 7.2.1 Electromagnetism, 7.2.2 Fleming's left-hand rule (HT only), 7.2.3 Electric motors (HT only), and 7.2.4 Loudspeakers (HT only). Each one has a worked solution and a mark scheme showing where the marks go.