MCQ
The power loss is less in transmission lines, when:
- AVoltage is less but current is more
- BBoth voltage and current are more
- CVoltage is more but current is less
- DBoth voltage and current are less
✓
Answer
- Voltage is more but current is less
Explanation:
The power cables have some resistance.
Power lost in the wires can be calculated as P = I2R with R as the resistance of the wires and I as the current that passes through them.
Power at the load is P = VI.
From this one can see that if voltage is increased by say n times, then only $\frac{1}{\text{n}}$ the current is required to deliver the same power. However, if $\frac{1}{\text{n}}$ current is passed
on the same wires, only $\frac{1}{\text{n}^2}$ of the power will be lost.
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