In the figure below, short sections of two very long parallel lines of charge ar
ID: 1433202 • Letter: I
Question
In the figure below, short sections of two very long parallel lines of charge are shown, fixed in place and separated by L = 7.0 cm. The uniform linear charge densities are +6.0 mu C/m for line 1 and -2.0 mu C/m for line 2. Where along the x axis shown is the net electric field from the two lines zero? The figure below is a section of a conducting rod of radius R_1 = 1.30 mm and length L = 11.00 m inside a thick-walled coaxial conducting cylindrical shell of radius R_2 = 10.0R_2 and the (same) length L. The net charge on the rod is Q_1 = +2.00 times 10^-12C that on the shell is Q_2 = -2.00Q_1.Explanation / Answer
E1 = 2*k*lambda1/r1
E2 = 2*k*lambda2/r2
suppose x is the point where E = 0
lambda1/(L/2 + x) = lambda2/(x - L/2)
6*(x - 3.5) = 2*(3.5 + x)
4x = 28
x = 7 cm from the origin
Let me know if you have any doubt.