Question

The electric potential inside a uniformly charged thin spherical shell of
radius 20 cm is 10 V. The charge on the shell is​

Answer 1

Given:

The electric potential inside a uniformly charged thin spherical shell of radius 20 cm is 10 V.

To find:

Charge on shell?

Calculation:

Let the charge on shell be "q".

• Now, we know that potential inside a shell is equal to the potential at the surface of the shell.

$V = \dfrac{kq}{r}$

$\implies 10= \dfrac{(9 \times {10}^{9} )q}{ (\frac{20}{100} )}$

$\implies 10= 4.5\times {10}^{10} \times q$

$\implies q = \dfrac{1}{4.5} \times {10}^{ - 9}$

$\implies q = 0.22 \times {10}^{ - 9} \: C$

$\implies q = 0.22 \: nC$

So, charge on shell is 0.22 nC.

Answer 2

Explanation:

Given:-

Radius=r=20cm

Electrical Potential Energy=V=10v

To find:-

Charge on the cell=Q

Solution:-

We know that

$\boxed{\sf V=\dfrac{kg}{r}}$

$\\ \sf\hookrightarrow 10=\dfrac{(9\times 10^9)Q}{\frac{20}{100}}$

$\\ \sf\hookrightarrow 10=\dfrac{(9\times10^{10})Q}{2}$

$\\ \sf\hookrightarrow 10=4.5\times 10^{10}Q$

$\\ \sf\hookrightarrow Q=\dfrac{1}{4.5}\times 10^{-9}$

$\\ \sf\hookrightarrow Q=0.22\times 10^{-9}C$

$\\ \sf\hookrightarrow Q=0.22nC$