Question

A single point charge is placed at the center of an imaginary cube that has 19 cm long edges. The electric flux out of one of the cube's sides is -2.5 kN·m2/C. How much charge is at the center? .................. nC

Answer 1

Answer:

The amount of charge at the center is -132.7 nC

Solution:

As per the question:

Electric flux from one face of cube, $\phi_{E} = - 2.5 kN.m^{2}/C$

Edge, a = 19cm

Since, a cube has six faces, thus total flux from all the 6 faces = $6\times (-2.5) = - 15 kN.m^{2}/C$

Also, from Gauss' law:

$\phi_{E,net} = \frac{1}{\epsilon_{o}}Q_{enc}$

$Q_{enc} = 8.85\times 10^{- 12}\times - 15\times 10^{3}$

$Q_{enc} = - 132.7 nC$