Question

Two charges of 15 pC and −40 pC are inside a cube with sides that are of 0.40-m length. Determine the net electric flux through the surface of the cube.

Answer 1

To solve this problem, we will apply the concepts related to Gaus' law that establishes that the electric flow through a surface is given by the charge of the object on the Vacuum permittivity. Mathematically this would be

$\phi = \frac{Q_{net}}{\epsilon_0}$

We must bear in mind that the net charge with the difference of the two charges given, therefore, replacing,

$\phi = \frac{(15-40)*10^{-12}C}{8.85*10^{-12}C^2/Nm^2}$

$\phi = 2.82WB$

Negative sign indicate flux is inward the surface