Ok, I see one error that i did. D should be:
\textbf{D} = \frac{Q_{inside}}{2\pi L r}\hat{r}
Similar steps as before gives me:
\frac{1}{\epsilon_1} \ln \frac{r_0+\delta}{r_0} = \frac{1}{\epsilon_2} \ln \frac{r_1}{r_0+\delta}
My remaining question is then how do i solve for δ in the equation...
Homework Statement
We have two coaxial cylinders with radius r0 and r1. The space between the two cylinders is completely coverd with two coaxial isolation layers with relative dielectric constants ε1 and ε2, ε1 is for the inner layer. Calculate the thickness of the inner layer such that the...
Ok, I got the right answer now. L could acctually be seen as large compared to a and b...
I'm so sorry for giving you guys the wrong information.
Still the mere fact that you said that you also found it hard to solve when L couldn't be seen as large made me rethink and get the right answer so...
Homework Statement
We have a discharge tube where the cathode is a cylinder with radius a and the anode is a coaxial cylinder with radius b, a<b. Both cylinders have length L, (Note that L can not be seen as large).The potential of the cathode is 0 and the potential of the anode is U>0. The...