Calculate the capacitance per unit length of the cable

[ndoc]

Homework Statement

The coaxial cable from a television or other device has an inner conductor with diameter of 1 mm and the shield of diameter 5 mm. Assume a plausible value for the dielectric constant (3 ≤ κ ≤ 5) of the dielectric separating the two conductors and calculate the capacitance per unit length of the cable.

Homework Equations

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The Attempt at a Solution

I am really unsure of how to even start this problem. The answer they are looking for is a range ____ nF/m <= C/L <= _____ nF/m. Thanks in advance!

 

[ideasrule]

Start by assuming that one unit length of the cable has a charge Q. What would be the potential difference across the shield?