Answer to Question #205846 in Electric Circuits for el john

Question

Draw the net electric force on a +1-C charge placed at the center of:

A line segment of length 1.0 m with a +1-C charge and a –1-C charge at its endpoints;

Answer 1

Force on center charge due to 1C toward negative charge, is,

$F=\frac{1}{4\pi\epsilon_0}\frac{q_1\times q_2}{r^2}=\frac{9 \times 10^9 \times 1 \times 1}{0.25}=36 \times 10^9N$

Force due to -1C will be attractive, towards -1C charge, is

$F'=\frac{1}{4\pi\epsilon_0}\frac{q_3\times q_2}{r^2}=\frac{9 \times 10^9 \times 1 \times 1}{0.25}=36 \times 10^9N$

This force will act towards the negative charge.

So, total force on center charge will be,

$F_T=F+F'=(36 \times 10^9) +( 36 \times 10^9 ) = 72 \times 10^9N$