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Question 2.13: Find the electric field a distance s from an infinitely long...

Find the electric field a distance s from an infinitely long straight wire that carries a uniform line charge λ. Compare Eq. 2.9.

E= \frac{1}{4\pi \varepsilon _0}\frac{2\lambda }{z}                    (2.9)

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\oint{} E·da = E ·2\pi s \cdot l=\frac{1}{\varepsilon _0}Q_{enc}=\frac{1}{\varepsilon _0} \lambda l. So

E=\frac{\lambda }{2\pi \varepsilon _0s} \hat{s}   (same as Eq. 2.9)

2.13

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