Same chapter3 marksDifficulty: Medium
What is the function of the earth wire and how does it protect the user?
Household Circuits
3 marksDifficulty: Medium
Why is a three-pin plug preferred to a two-pin plug for a metal-bodied appliance?
Original Khojo Papers practice question — not from a past board paper.
Answer
A three-pin plug carries an earth pin as well as live and neutral, so the metal body of the appliance can be earthed. With a two-pin plug there is no earth connection, and if the live wire touched the body it would stay live and give a shock to anyone touching it.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The earth pin is longer and thicker so that it makes contact first and breaks contact last.
Related questions
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Same chapter1 markDifficulty: Medium
The colour of the earth wire in the modern convention is:
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Same chapter2 marksDifficulty: Easy
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Same chapter2 marksDifficulty: Easy
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