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Note that your final mark will not be saved in the system.

Power supplies GapFill

Target Level
4-5
Running Total
0
0%
Attempt
1 of 3

You must fill all the gaps before clicking ‘Check Answers!’

Domestic electrical appliances use mains electricity. This has an alternating potential difference with a value of  230 V50 V120 V100 V, at a frequency of  100 Hz120 Hz50 Hz230 Hz.
Mains electricity is delivered by three-core cables, which consist of the  staticneutraldirectlive wire, which provides the potential difference, the  staticliveneutraldirect wire, which completes the circuit, and the  directstaticliveearth wire, which is for safety purposes and only carries a current if there is a fault in the appliance.
Circuits transfer power at a rate equal to P = VI, or  P = I²RP = IR²P = I ÷ R²P = R ÷ I². The total energy transferred by a component is equal to  E = QVE = Q ÷ VE = QV²E = Q ÷ V².
Mains electricity is delivered by the National Grid, which connects power stations to homes and businesses. At power stations, the potential difference of the electricity is increased using  step-down transformersdrop-down generatorsboost-up generatorsstep-up transformers for transmission, and in homes the potential difference is decreased using  boost-up generatorsdrop-down generatorsstep-up transformersstep-down transformers for use by appliances.

This is your 1st attempt! You get 3 marks for each one you get right. Good luck!

Pass Mark
72%