Same chapter3 marksDifficulty: Medium
On what factors does the resistance of a wire depend, and how?
Current Electricity
3 marksDifficulty: Medium
Why are the lamps in a house wired in parallel and not in series?
Original Khojo Papers practice question — not from a past board paper.
Answer
In parallel every lamp gets the full mains voltage, so each works at its rated brightness, and each can be switched on and off independently. If one lamp fails the others still work, because each has its own complete path to the supply. In series they would share the voltage, all would have to be on together, and one failure would break the whole circuit.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The total current drawn is larger in parallel, which is why the supply cable must be thick.
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