Two copper conductors have equal lengths. The cross-sectional area of one conductor is four times that of the other. If the conductor having a smaller cross-sectional area has a resistance of 40 ohms, the resistance of the other conductor will be
Correct answer: D. 10 Ohms
- A. 160 Ohms
- B. 80 Ohms
- C. 20 Ohms
- D. 10 Ohms
Explanation
The resistance of the conductor is given by: R = ρ/AAs the area of cross section increases, resistance decreases.Resistance of thin wire = 40 ΩResistance of thick wire = 40/4 = 10 Ω
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Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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