Question

The electric flux passing through $a$ cube of side $ a $ , which holds a charge $ q $ at one of its corners is

• A. $ \frac{q}{\varepsilon_{0}} $
• B. $ \frac{q}{8\varepsilon_{0}} $
• C. $ \frac{q}{4\varepsilon_{0}} $
• D. $ \frac{q}{2\varepsilon_{0}} $

Answer 1

Answer: (B)

Eight identical cubes are required so that the given charge $q$ appears at the centre of the bigger cube
Thus, the electric flux passing through the given cube is
$\phi=\frac{1}{8} \left(\frac{q}{\varepsilon_{0}}\right)$
$=\frac{q}{8\varepsilon_{0}}$