UK Mains Supply — Key Facts

Part of Mains Electricity & Safety · Section 2 of 16

Deep DiveUnit: ElectricityGCSE

This deep dive covers UK Mains Supply — Key Facts within Mains Electricity & Safety for GCSE Physics. Revise Mains Electricity & Safety in Electricity for GCSE Physics with 18 exam-style questions and 30 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 2 of 16 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

📚 UK Mains Supply — Key Facts

Essential values (memorise these):

  • Voltage: 230 V
  • Frequency: 50 Hz (alternates 50 times per second)
  • Type: AC (alternating current)

AC vs DC:

  • AC (alternating current) — direction reverses constantly; used for mains power
  • DC (direct current) — flows in one direction only; batteries provide DC

Why AC for mains? AC voltage can be easily changed using transformers — stepped up for efficient long-distance transmission, stepped down for safe household use.

Practice questions for Mains Electricity & Safety

What does AC stand for, and how does it differ from DC?

  • A. Alternating current; it flows at a higher voltage than DC
  • B. Alternating current; it repeatedly changes direction, whereas DC flows in one direction only
  • C. Adapted current; it is produced only by batteries
  • D. Alternating current; it flows at a constant rate, whereas DC changes direction
1 markfoundation

Explain how a fuse protects an electrical circuit from damage.

2 marksstandard

Quick recall flashcards

What is DC?
Direct Current — current flows in one direction only (batteries provide DC)
What is AC?
Alternating Current — current direction reverses constantly (50 times/second in UK)

18 questions on Mains Electricity & Safety — practise free

Instant marking, adaptive difficulty and spaced-repetition flashcards — all aligned to your exam board.

Start revising free →