Answer to Question #185214 in Field Theory for Esmail

Question

In the following figure, a rod of Length L=8cm has negative charge q = -4fC uniformly

distributed along its length. a) What is the linear charge density of the rod? b) What are the

magnitude and direction of the electric field produced at point P, at a distance d = 10cm from the rod?

Answer 1

a)

$$\lambda=\frac{-4\cdot10^{-15}}{0.08}=-5\cdot10^{-14}\frac{C}{m}$$

b)

$$E=\frac{2k\lambda}{r}\\E=\frac{2(9\cdot10^{9})(5\cdot10^{-14})}{0.1}=0.009\frac{V}{m}$$

Negative direction.