USING TRANSFORMERS TO CHANGE VOLTAGES
2 marks · EasyExplain briefly why a transformer is needed to distribute electricity over long distances.
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Must show: Voltage must be increased to reduce energy loss, A transformer increases voltage for efficient transmission
Also accept: Transformers increase the voltage to reduce energy lost as heat in the cables during long-distance transmission.
Common mistakes: Transformers are used to decrease voltage for transmission
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Marking points
B1 · 1 mark · States that increasing voltage reduces energy loss in cables.
B2 · 1 mark · Mentions the use of a (step-up) transformer to increase voltage.
Worked solution
A transformer is used to increase the voltage before transmission. High voltage reduces current, so less energy is lost as heat in the wires during transmission over long distances.