Question

Question:When calculating line capacitance, it is normal practice to replace a stranded conductor by a perfectly conducting solid cylindrical conductor whose radius equals the outside radius of the stranded conductor.

(a) True

(b) False

Short answer

Answer

Therefore the correct option is (a) True.

Step-by-step solution

Define the line capacitance

While determining the line capacitance, the conductor voltages and conductor charges must be known beforehand. Thus, to determine theses parameters, the induced charges on stranded conductors are replaced by a perfectly conducting surface to account the induction.

Thus, the maximum capacitance at the surface of one conductor is calculated easily. The reason being the most of the capacitance is present due to outer surface of the conductor.

Explain effect of non-uniform charge distribution 

The replacement of the stranded conductor by the perfect conductor gives approximately correct calculation of capacitance. The reason being that the charge distributed on the conducting surface is non uniform in nature. So, the stranded conductor and perfect conductor gives almost same charge distribution as inner conductor of stranded conductor have very less induced charge.

The non-uniform distribution of the charge on the inner conductor is experimentally shown to have a very negligible effect on line capacitance as it possess low number of charges and millimeter distance from the outer conductor.

Hence the correct option (a).