An offshore wind farm generates alternating current at 33 kV33\ \text{kV}33 kV. It must transfer a fixed electrical power to the mainland through a long undersea cable.
Three transformers are available. The primary potential difference of each transformer is 33 kV33\ \text{kV}33 kV.
| Transformer | Secondary potential difference |
|---|---|
| P | 11 kV11\ \text{kV}11 kV |
| Q | 33 kV33\ \text{kV}33 kV |
| R | 275 kV275\ \text{kV}275 kV |
Explain which of the three transformers should be connected between the wind farm and 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.