Topic 13: Electromagnetic induction – GCSE Edexcel Foundation Combined Science Physics revision notes

Electromagnetic induction, transformers and the National Grid. 2 lessons in 1 subtopic.

The National Grid is a system of cables and transformers linking power stations to consumers across the country. The National Grid Introduction notes cover this in full.

A power station is a facility that generates electrical energy from various sources like fossil fuels, nuclear power, or renewable sources such as wind and solar. The National Grid Introduction notes cover this in full.

A step-up transformer increases voltage from the primary coil to the secondary coil, because the secondary coil has more turns than the primary coil. The Transformers and Efficiency in the National Grid notes cover this in full.

Power stations generate electricity at around 25,000 volts, which is stepped up to 400,000 volts for long-distance transmission. The National Grid Introduction notes cover this in full.

A step-down transformer decreases voltage from the primary coil to the secondary coil, because the secondary coil has fewer turns than the primary coil. The Transformers and Efficiency in the National Grid notes cover this in full.

Transformers only work with alternating current because they rely on changing magnetic fields. The Transformers and Efficiency in the National Grid notes cover this in full.

A step-up transformer does not increase both voltage and current: if voltage goes up, current must go down, because for an ideal transformer power in equals power out. The Transformers and Efficiency in the National Grid notes cover this in full.

The National Grid consists of high-voltage cables, which carry electricity over long distances, and transformers, which change the voltage at different points in the journey. The National Grid Introduction notes cover this in full.