[2008EM/HMW-03]

IMSc-IV Physics-IV : Electricity and Magnetism Jan-Apr 2008 
Set-IV : Tutorial-III
 Electric Potential

• Four charges $q,2q,-q,-2q$ are placed at the corners of a square of side $a$. Find the electric field at a point distance $z$ above the center of the square. \input{\QBankDir/em-que-01016}
• The electric field due to a line segment of length $2L$, and carrying a uniform line charge $\lambda$ at a distance $d$ above the mid point is given by $$ E = \frac{1}{4\pi\epsilon_0} \, \frac{2\lambda L}{d \sqrt{d^2 +L^2}}$$ Using the above result find the electric field at a distance $z$ above the center of a square loop ( side $2L$) carrying a uniform line charge $\lambda$.