NEETPhysicsCurrent ElectricityMCQ+4 / −1
Two cities are 150 km apart. Electric power is sent from one city to another city through copper wires. The fall of potential per km is 8 volt and the average resistance per km is 0.5 . The power loss in the wire is
- A19.2 W
- B19.2 kW
- C19.2 J
- D12.2 kW
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Correct answer: B
Total voltage drop across the wire : V = 150 × 8= 1200 volt
Total resistance of wire, (R) = 150 × 0.5 = 75
Hence, current through wire
I = V/R
I = 1200/75 =16 A
Finally the power loss will be,
P = I2R = (16)2 × 75
= 19200 W or 19.2 kW
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