capacitance per length of co-axial cabel

[trans_pie]

Find the capacitance per length of a co-axial cable with a conductor of radius a and a thin shield of
radius b.

[Defennder]

Again, what have you done so far? Think of terms of Gauss law.

[trans_pie]

i got the answer 2π€/ln(b/a)

is it correct?

[Defennder]

Yep, should be.