Topic 2b - domestic electricity ( 3. the national grid )

Question 1

WHAT IS THE NATIONAL grid

Answer 1

network of cables and transformers that covers the UK and connects power stations to consumers. NG transfers electrical power from power stations anywhere on the grid to anywhere else on the grid where it is needed.

Question 2

what is a transformer

Answer 2

a device used in the national grid to change the pd of an electrical supply.

Question 3

what is the difference between a step up and step down transformer

Answer 3

transformers need to step up the pd at one end for efficient transmission . pd is increased using step up transformer. pd is decreased using step down transformer.

Question 4

how does the national grid meet the demand of electricity needed everyday

Answer 4

demand increases when people get up in the morning and when it starts to get cold and dark outside.

Question 5

how does current flow through a transformer

Answer 5

made up of 2 coils, primary and secondary, wrapped around an iron core, when current flows through primary causes current to flow through secondary.

Question 6

what formula is there to remember about the primary and secondary coil

Answer 6

vs + Is = vp + Ip

vs, Is is the power output at the secondary coil, and vp, Ip is the power input at the primary coil.

Question 7

what formula is there to remember about the primary and secondary coil

Answer 7

vs + Is = vp + Ip

vs, Is is the power output at the secondary coil, and vp, Ip is the power input at the primary coil.