Topic 2 The National Grid

Question 1

What is the national grid

Answer 1

A giant system of cables and transformers that cover the uk and connect power stations to consumers

Question 2

What does the national grid transfer

Answer 2

Electrical power from power statins to suppliers

Question 3

Step up transformer

Answer 3

More turns in secondary coil
Pd increase
Current decrease

Question 4

Step down transformer

Answer 4

More turns on primary coil
Increase current
Lower pd

Question 5

When a demands increased

Answer 5

When people get up in the morning
Come home from school/work
When it gets dark or cold
For popular events

Question 6

What do power stations do to make sure their is spare capacity to cope with high demand

Answer 6

Run well below their maximum power output

Question 7

What else can be dome in case of high demands

Answer 7

Keep smaller power stations on standby

Question 8

Which is cheaper to boost pd or current

Answer 8

Pd

Question 9

What does increasing the pd and decreasing the current do

Answer 9

Reduce the amount of energy lost by heating the wire and the surroundings and makes the national grid more efficient

Question 10

What is the best pd for efficient transmisión

Answer 10

400000

Question 11

Why is power in primary coil = power in secondary coil

Answer 11

Transformers are nearly 100% efficient