Electric Field and Surface Charge Density of Concentric Dielectric Shell

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The discussion revolves around calculating the electric field and surface charge density for a cylindrical charge distribution and a concentric dielectric shell. The charge density is given as ρ = α/√r, with α specified, and the problem requires finding the electric field at various distances from the center. Gauss's Law is applied to relate the electric field to the charge enclosed, but the user struggled with the calculations and obtaining the correct answers. The provided answers for the electric field at specified points and the surface charge density on the inner surface of the dielectric are noted. The user seeks advice on improving clarity in their problem presentation and understanding the solutions.
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Homework Statement


A cylindrical distribution of charge \rho=\frac{\alpha}{\sqrt{r}}[\tex] <br /> where [ tex ]\alpha = \frac{2\muC}{m^\frac{5}{2}} [ \tex ] extends from 0 cm to 8.2 cm. Concentric with this is a dielectric shell with 4.08 of inner radius 16 cm and other radius 26 cm. What is the electric field at 3.81 cm, 13 cm, 20.1 cm, and 34.7 cm? What is the surface charge density on the inner surface of the dielectric?<br /> <br /> There was no picture provided.<br /> <br /> <h2>Homework Equations</h2><br /> Gauss&#039;s Law <br /> <br /> <h2>The Attempt at a Solution</h2><br /> I was really confused about what this problem was asking, especially since no picture was provided. For the length of the cylindrical charge and the dielectric shell, I tried using the value given. For example, while trying to solve for the electric field at 3.81 cm, I substituted 3.81 cm for the lengths. I tried using Gauss&#039;s Law, by multiplying E by 2*pi*r*l and setting this equal to the charge enclosed over (8.85*10^-12). For the charge enclosed, I solved for it, by plugging .0381 m into charge density formula and multiplying the result by the volume of the cylinder. I wasn&#039;t able to get the right answer.<br /> <br /> The answers in order are: 29393.6 V/m, 27199.9 V/m, 4311.76 V/m, 10190.2 V/m, -0.147717 C/m^2<br /> <br /> This is my first time posting here, and using Latex, so if anybody has any tips or advice on how I can make myself more concise and clear as well as how to fix what I was trying to display, I&#039;d really appreciate those as well.
 
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