Same chapter3 marksDifficulty: Medium
On what factors does the resistance of a wire depend, and how?
Current Electricity
3 marksDifficulty: Medium
Why are the connecting wires in a circuit made thick and short, while the element of a heater is made long and thin?
Original Khojo Papers practice question — not from a past board paper.
Answer
A thick short wire has a low resistance, so little energy is wasted as heat in the connections. A long thin element has a high resistance, so a large amount of heat is produced in it, which is exactly what a heater is for.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Resistance is proportional to length and inversely proportional to area of cross-section.
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