A Town Situated 20 Km Away From A Power Plant Generating Power At 440 V, Requires 600 KW Of Electric Power At 200 V. The Resistance Of The Two-wire Line Carrying Power Is  /km. The Town Gets Power From The Line Through A 3000-220 V Step-down Transformer At A Sub-station In The Town. Estimate The Line Power Loss As Heat.  

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A town situated 20 km away from a power plant generating power at 440 V, requires 600 kW of electric power at 200 V. The resistance of the two-wire line carrying power is  /km. The town gets power from the line through a 3000-220 V step-down transformer at a sub-station in the town. Estimate the line power loss as heat.  


Correct option is

640 W

The total length of the line wire is . Therefore, the resistance of the two-wire line is


The 600 kW power is transmitted at 3000 V through the line. Thus, therms current in the line is  


The line power loss is  




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