Question 836: Electrostats & Capacitance

Question

A uniformly charged conducting sphere of diameter 14 cm has surface charge density of $40 \mu \mathrm{Cm}^{-2}$. The total electric flux leaving the surface of the sphere is nearly (Permittivity of free space $=8.85 	imes 10^{-12}$ SI unit)

Accepted Answer

$$\begin{aligned}
	ext { Electric flux } \phi & =\frac{\mathrm{q}}{\varepsilon_0}=\frac{4 \pi \mathrm{r}^2 \sigma}{\varepsilon_0} \
& =\frac{4 	imes 3.14 	imes\left(7 	imes 10^{-2}ight)^2 	imes 40 	imes 10^{-6}}{8.85 	imes 10^{-12}} \
& =\frac{4 	imes 3.14 	imes 49 	imes 10^{-4} 	imes 4 	imes 10^{-5}}{8.85 	imes 10^{-12}} \
& =\frac{4 	imes 3.14 	imes 49 	imes 4 	imes 10^3}{8.85} \
& =278 	imes 10^3 \approx 280 	imes 10^3 \mathrm{~Wb} \
& =280 \mathrm{~kWb}
\end{aligned}$$

Answer

40 kWb

Answer

140 kWb

Answer

240 kWb

Answer

280 kWb

Electrostats & Capacitance

A uniformly charged conducting sphere of diameter 14 cm has surface charge density of 40 \mu \mathrm{Cm}^{-2}. The total electric flux leaving the surface of the sphere is nearly (Permittivity of free space =8.85 \times 10^{-12} SI unit)

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