Question 108: AC fundamentals

Question

A telegraph line of length 100 km has a capacity of 0.01 $$\mu$$F/km and it carries an alternating current at 0.5 kilo cycle per second. If minimum impedance is required, then the value of the inductance that needs to be introduced in series is _____________ mH. (if $$\pi$$ = $$\sqrt{10}$$)

Accepted Answer

Total capacitance = 0.01 $$	imes$$ 100 = 1 $$\mu$$F
$$\omega$$ = 500 $$	imes$$ 2$$\pi$$ = 1000$$\pi$$ rad/s
$$\omega L = {1 \over {\omega C}}$$
$$ \Rightarrow L = {1 \over {{\omega ^2}C}} = {1 \over {{{10}^6}{\pi ^2} 	imes {{10}^{ - 6}}}} = {1 \over {10}}H$$ = 100 mH

AC fundamentals

A telegraph line of length 100 km has a capacity of 0.01 $\muF/km and it carries an alternating current at 0.5 kilo cycle per second. If minimum impedance is required, then the value of the inductance that needs to be introduced in series is _____________ mH. (if \pi = \sqrt{10}$)

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