When current flows through heater coil it glows but supply wiring does not glow because______________?
Correct answer: C. resistance of heater coil is more than the supply wires
- A. current through supply line flows at slower speed
- B. supply wiring is covered with insulation layer
- C. resistance of heater coil is more than the supply wires
- D. supply wires are made of superior material
Explanation
The same current flows through the heater and its supply wires, but heating power is proportional to I²R. The heater coil has much greater resistance, so it becomes hot and glows while the low-resistance wires do not.
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