What is the purpose of the earth wire connected to the metal case of an appliance?
Answer and explanation
Correct answer: D. To carry a fault current safely to the ground
If the live wire touches the case, the earth wire provides a path to the ground so that the fuse blows and the user is safe.
Answer: To carry a fault current safely to the ground.
Why not the others: To increase the current to the appliance: it carries no current in normal use. To reduce the voltage of the supply: it does not change the supply voltage. To make the appliance work faster: it plays no part in normal operation.
Answer: To carry a fault current safely to the ground.
Why not the others: To increase the current to the appliance: it carries no current in normal use. To reduce the voltage of the supply: it does not change the supply voltage. To make the appliance work faster: it plays no part in normal operation.
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