A student investigates how the force on a wire depends on the current in it. The wire is at right angles to a magnetic field. The length of wire in the field is 0.10 m.
Table
| Current (A) | Force (N) |
|---|---|
| 1.0 | 0.020 |
| 2.0 | 0.040 |
| 3.0 | 0.060 |
| 4.0 | 0.080 |
What is the magnetic flux density of the field?
0.20 T0.20\ \text{T}0.20 T
0.020 T0.020\ \text{T}0.020 T
2.0 T2.0\ \text{T}2.0 T
0.0020 T0.0020\ \text{T}0.0020 T
48 exam-style questions on OCR GCSE Physics 4.2 Uses of magnetism, covering 4.2.1 The motor effect, 4.2.2 Fleming's left-hand rule, 4.2.3 The force on a current-carrying conductor, 4.2.4 The electric motor, 4.2.5 Electromagnetic induction, 4.2.6 Alternators and dynamos, 4.2.7 How transformers work, 4.2.8 Transformer turns ratio, 4.2.9 Potential differences and turns in transformers, and 4.2.10 Microphones, loudspeakers and headphones. Each one has a worked solution and a mark scheme showing where the marks go.