Question

If a uniformly charged spherical shell of radius $10cm$ has potential $V$ at a point distant $5cm$ from its center, then the potential at a point distant $15cm$ from the center will be:

• A. $\frac{V}{3}$
• B. $\frac{2V}{3}$
• C. $\frac{3}{2}V$
• D. $3V$

Answer 1

The correct option is B $\frac{2V}{3}$

Potential inside conducting sphere

$=\frac{KQ}{R}\to$ radius of shell

Potential outside a conducting sphere

$=\frac{KQ}{r}$

$r=$ dist upto that point

So, V at point dist $5cm$

$=\frac{KQ}{10}$

$Vat15cm$

$\frac{KQ}{15}$

$\frac{V}{V_1}=\frac{KQ/10}{KQ/15}=\frac{15}{10}$

$V^1=\frac{2}{3}V$