National Grid + Mains

Question 1

What is the national grid?

Answer 1

A system of cables and transformers linking power stations to consumers

Question 2

What are step up transformers used for?

Answer 2

• to increase the potential difference from the power stations to the transmition cables

Question 3

What are step down transformers used for?

Answer 3

• used to decrease the potential difference from transmition cables to houses

Question 4

Why is the national grid system an efficient way to transfer energy?

Answer 4

• current and potential difference are directly proportional
• high currents in a wire dissipate lots of energy
• by transporting energy through transmition cables at high potential difference / voltage and a low current, less energy is dissipated
• step up and step down transformers just make the energy safe for homes and buildings