A tidal power station transfers electrical power to the mainland through an undersea cable. The generator provides an alternating potential difference to a transformer that is 100% efficient. The secondary coil is connected to the undersea cable.
| Quantity | Value |
|---|---|
| primary potential difference | 33 000 V33\,000\ \text{V}33000 V |
| primary current | 2400 A |
| number of turns on the primary coil | 600 |
| number of turns on the secondary coil | 3000 |
| total resistance of the undersea cable | 2.5 Ω |
Calculate the current in the undersea cable.
Calculate the percentage of the input power that is dissipated in the undersea cable.
The secondary coil is replaced with a coil of 6000 turns. The primary potential difference and primary current remain unchanged, and no other change is made to the system.
Explain how this change affects the power dissipated in the undersea cable.
108 exam-style questions on Edexcel GCSE Physics 13.2 Transformers and the National Grid, covering 13.2.1 Transformers and induction, 13.2.2 The transformer turns-ratio equation, 13.2.3 The National Grid, 13.2.4 The transformer power equation, and 13.2.5 Advantages of high-voltage transmission. Each one has a worked solution and a mark scheme showing where the marks go.