Question

A uniformly charged sphere carries a total charge
of 2π x 10-12C. Its radius is 5 cm and is placed in
vacuum. Determine its surface charge density.​

Answer 1

$\underline{ \huge \boxed{ \bold{ \mathfrak{ \purple{Answer}}}}}$

Surface density is defined as charge per unit area.

$\: \: \: \: \: \: \: \: \: \: \: \: \dag \: \underline{ \boxed{ \bold{ \rm{ \pink{ \sigma = \frac{charge}{area}}}}}} \: \dag$

Calculation :

$\leadsto \rm \: \sigma = \frac{2\pi \times {10}^{ - 12} \times {10}^{4} }{4\pi {(5)}^{2} } \\ \\ \therefore \: \underline{ \boxed{ \bold{ \orange{ \rm{ \sigma = 2 \times {10}^{ - 10} \frac{c}{ {m}^{2} } }}}}} \: \red{ \clubsuit}$

Answer 2

Explanation:

surface density is defined as charge per unit area.

σ = charge/area

Calculation:

σ = 2π × 10^(-12) ×10^4/4π×5^2

∵ σ = 2 × 10^(-10) C/m^2