Question

An over head line having surge impedance of $400\Omega$ is connected in series with an underground cable having a surge impedance of $50\Omega$. If a surge of 100 kV travels from the line towards the cable junction. The coefficient of refraction of voltage at the junction of cable and overload line is ____.

• A. 0.222

Answer 1

The correct option is A 0.222

$Coefficientofrefractionforvoltage=\frac{2Z_2}{Z_1+Z_2}=\frac{2\times 50}{50+400}$

= 0.222