Same chapter3 marksDifficulty: Medium
On what factors does the resistance of a wire depend, and how?
Current Electricity
3 marksDifficulty: Medium
An electric heater of resistance 20 Ω draws a current of 5 A. Calculate the heat produced in 2 minutes.
Original Khojo Papers practice question — not from a past board paper.
Answer
60 000 J (60 kJ)
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Heat produced = I2Rt = 52 × 20 × 120 = 25 × 20 × 120 = 60 000 J.
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