Walker, Halliday & Resnick — Electric Potential: Problem 6

6 The thin plastic rod of length \(L = 12.0 \text{ cm}\) in Fig. 24-24 has a nonuniform linear charge density \(\lambda = cx\), where \(c = 49.9 \text{ pC/m}^2\). (a) With \(V = 0\) at infinity, find the electric potential at point \(P_2\) on the \(y\) axis at \(y = D = 3.56 \text{ cm}\). (b) Find the electric field component \(E_y\) at \(P_2\). (c) Why cannot the field component \(E_x\) at \(P_2\) be found using the result of (a)?