Module 2 : Electrostatics
Lecture 8 : Properties Of Conductors
  Example 10 :
  Calculate the electric field outside a conductor carrying a surface charge density $\sigma$.
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  Take a gaussian pillbox in the shape of a cylinder of height $h$ with $h/2$inside and $h/2$outside the conductor. Lat the cross sectional area be $dS$normal to the surface. The electric field is normal to the surface. As the field inside is zero and there is no tangential component of the field at the surface, the flux goes out only through the outer cap of the cylider. The charge enclosed is $\sigma dS$and the flux is $E dS$. The electric field is normal to the surface. applyinng Gauss's law
 
\begin{displaymath}E =\frac{ \sigma}{\epsilon_0}\hat n\end{displaymath}
   

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