Question

Careful measurement of the electric field at the surface of a black box indicates that the net outward flux through the surface of the box is $8.0\times {10}^{3}N{m}^2/C$. What is the net charge inside the box?

• A. $0.05\mu C$
• B. $0.06\mu C$
• C. $0.07\mu C$
• D. $0.08\mu C$

Answer 1

The correct option is C $0.07\mu C$

Apply Gauss's law
$\varphi =\frac{q}{{ϵ}_0}\Rightarrow q=0.07\mu C$