Question

Find the flux of the electric field through a spherical surface of radius R due to a charge of $10-7C$ at the centre and another equal charge at a point 2R away from the centre (figure 30-E2).the point P, the flux of the electric field through the closed surface

(a) will remain zero (b) will become positive

(c) will become negative (d) will become undefined .

Answer 1

Given : magnitude of the two charges placed $={10}^{-7}C$

We know from Gauss's law that the flux experienced by the sphere is only by due to internal charge and not by the external one.

NOw,

$E\times ds=\frac{Q}{{\in }_0}=\frac{{10}^{-7}}{8.85}\times {10}^{+12}$

$=1.1\times {10}^{4}N-m/C$