Figure 8 shows how electricity is supplied to consumers by the National Grid.
I- Explain why transformer X is used in the National Grid.
[4 marks]
SOLUTION
Transformer X increases potential difference & decreases current. By keeping the current low, less energy is wasted in the form of heat and the whole system is much more efficient.
II- Explain why transformer Y is used in the National Grid.
[2 marks]
SOLUTION
Transformer Y lowers the potential difference (and increases current) to a safer value.
III- The town of Hornsdale in Australia has electricity supplied by a huge battery.
On one day the battery transferred
The potential difference of the town’s electricity supply is 230 V.
Calculate the charge flow to the town on this day. Use the Physics Equations Sheet.
Give your answer to 3 significant figures.
[ 4 marks]
SOLUTION
Making Q as the subject.
