Question

Electric Fields, Flux and Gauss' Law.

Help me please to answer on these questions. Thank you!

is the net electric flux through the closed surface in each case shown below? Assume that 5 lines leave a charge of +q or terminate on a charge of -q. (Assume that all of the surfaces are three-dimensional.) Use the net number of field lines leaving the 4. What suirtuce as a meusure of flux. Explain in the spuces below how you arrived at your answers b. C. tq +2q e3g +2q -3q d. +2q -q a. b. C. d. 5. How does Gauss' law explain that excess charge on a conductor must reside on the outside surface?

Answer 1

Since we know that, Gauss' Law states that, Electric flux passing through closed surface is 1/epsilon_0 times of charge enclosed by closed surface Mathematically phi = contourintegral E vector. ds vector = q_en/epsilon_0 oR Electric flux also defined as, the no of electric field lines leaving or entering in the closed surface is equal to electric flux. According to Gauss' law phi = q_en/epsilon_0 = 5 {Because according to question 5 lines leaves a charge of + q} phi_a = q/epsilon_0 where epsilon_0 = absolute permittivity of force space = 8.85 times 10^-12 c^2/Nm^2 Similarly in part b \r\n psi_b = q_en/epsilon_s = q + 2q - 3q/epsilon = 0 psi_b = 0 psi_c = 2q - 3 q/epsilon psi_c = -epsilon/epsilon -ve sign indicates electric field lines are entering into the surface. psi_d = q_en/epsilon_0 psi_d = 0 {since q_en = 0} Since electric field inside a conductor is always zero. Therefore, if there is any charge