Cables transmit electrical power from the output of the transformer at a power station to the input of the transformer at a substation.
The power at the output of the transformer at the power station is 300 MW300\text{ MW}300 MW.
Which combination of potential difference at the power station transformer output and thickness of the cables results in the greatest power loss in the transmission cables?
150 kV150\text{ kV}150 kV and thin
150 kV150\text{ kV}150 kV and thick
300 kV300\text{ kV}300 kV and thin
300 kV300\text{ kV}300 kV and thick
452 exam-style questions on CIE IGCSE Physics 4.2 Electrical quantities, covering 4.2.1a Positive and negative charge, 4.2.1b Charging by friction and detecting charge, 4.2.1c Electrical conductors and insulators, 4.2.1d Electric fields and electric field patterns, 4.2.2a Electric current, charge and measuring current, 4.2.2b Conduction in metals and the direction of current, 4.2.2c Direct current and alternating current, 4.2.3a Electromotive force, 4.2.3b Potential difference and voltmeters, 4.2.4a Resistance, 4.2.4b Resistance of a metallic wire, 4.2.4c Current–voltage graphs, and 4.2.5 Electrical energy and electrical power. Each one has a worked solution and a mark scheme showing where the marks go.