$A$ uniformly charged conducting sphere of $2.4\; m$ diameter has a surface charge density of $80.0\; \mu C/m^2$.
$(a)$ Find the charge on the sphere.
$(b)$ What is the total electric flux leaving the surface of the sphere?

(N/A) Diameter of the sphere,$d = 2.4\; m$.
Radius of the sphere,$r = 1.2\; m$.
Surface charge density,$\sigma = 80.0\; \mu C/m^2 = 80 \times 10^{-6}\; C/m^2$.
Total charge on the surface of the sphere,$Q = \text{Charge density} \times \text{Surface area} = \sigma \times 4\pi r^2 = 80 \times 10^{-6} \times 4 \times 3.14159 \times (1.2)^2 \approx 1.447 \times 10^{-3}\; C$.
Therefore,the charge on the sphere is $1.447 \times 10^{-3}\; C$.
$(b)$ Total electric flux $(\phi_{\text{total}})$ leaving the surface of a sphere containing net charge $Q$ is given by Gauss's Law,$\phi_{\text{total}} = \frac{Q}{\varepsilon_0}$.
Where,$\varepsilon_0 = 8.854 \times 10^{-12}\; C^2 N^{-1} m^{-2}$.
$\phi_{\text{total}} = \frac{1.447 \times 10^{-3}}{8.854 \times 10^{-12}} \approx 1.634 \times 10^8\; N C^{-1} m^2$.
Therefore,the total electric flux leaving the surface of the sphere is $1.634 \times 10^8\; N C^{-1} m^2$.