Question

Electric power is transmitted over long distances through conducting wires at high voltage because

• A. High voltage travels faster
• B. Power loss is large
• C. Power loss is less
• D. Generator produced electrical energy at a very high voltage

Answer 1

Answer: (C)

Power loss is less

It is known that $H=\frac{V^{2}t}{4.2R}$ or $\frac{H}{t}=\frac{V^2}{4.2}R$

According to question:

$\Rightarrow 800=\frac{20\times 20}{4.2\times R}\Rightarrow R=\frac{5}{42}=0.119\approx 0.12\Omega$