A uniformly charged conducting sphere of radius 1.3 m has a surface charge density of $70 μC\, m^{-2}$. What is the total electric flux leaving the surface of the sphere?

$1.7×10^8 N\, m^2\, C^{-1}$

The correct answer is Option (3) → $1.7×10^8 N\, m^2\, C^{-1}$

According to Gauss's law,

$\phi_E=\frac{q_{enclosed}}{ε_0}$

$=\frac{70×10^{-6}×4×\pi×(1.39)^2}{8.85×10^{-12}}$

$≃1.7×10^8 N\, m^2\, C^{-1}$