Question
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 twowire line carrying power is /km. The town gets power from the line through a 3000220 V stepdown transformer at a substation in the town. Estimate the line power loss as heat.

650 W

640 W

655 W

None of these
easy
Solution
640 W
The total length of the line wire is . Therefore, the resistance of the twowire 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
.
SIMILAR QUESTIONS
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