An electricity substation uses a transformer to step up voltage for long-distance transmission across the national grid. The table below lists the potential difference (p.d.) and current for the primary and secondary coils of four prototype transformers under test.
Which row displays the correct data for an ideal step-up transformer?
| Primary coil p.d. | Primary coil current | Secondary coil p.d. | Secondary coil current | |
|---|---|---|---|---|
| A | 400 kV400 \text{ kV}400 kV | 80 A | 20 kV20 \text{ kV}20 kV | 1600 A |
| B | 20 kV20 \text{ kV}20 kV | 80 A | 400 kV400 \text{ kV}400 kV | 1600 A |
| C | 20 kV20 \text{ kV}20 kV | 1600 A | 400 kV400 \text{ kV}400 kV | 80 A |
| D | 20 kV20 \text{ kV}20 kV | 1600 A | 20 kV20 \text{ kV}20 kV | 1600 A |
Row A
Row B
Row C
Row D
16 exam-style questions on OCR GCSE Physics Uses of magnetism. Each one has a worked solution and a mark scheme showing where the marks go.