(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A single phase transmission line has 2 parallel conductors 1.5 metres apart. The diameter of each conductor being 0.5 cm. Calculate the line to neutral capacitance for a line 80 km long

2. Relevant equations

C_{AN}= 2(3.14)(permittivity)/Log_{e}[D/r] This gives capacitance per metre

Where D is the distance between conductors and r is the radius.

Multiplying above answer into length of line gives capacitance

3. The attempt at a solution

D = 1.5 metres = 150 cm

r = radius = 0.5 / 2 = 0.25 cm

Substituting in above equation I get C_{AN}= 8.69 * 10^{-12}F / m

Multiplying this with 80 km or 80,000 m I get 0.69 micro farad.

Book answer is 3.48 micro farad

I guess they've used formula for line capacitance C_{AB}instead of line to neutral capactiance.

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# Homework Help: Capacitance of a Transmission line

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