Two spherical shells of radius 20 cm and 10 cm, having same charge of 150 `mu`C each are connected by means of a conducting wire. What will be their common potential ?

Options

A. `9xx10^(6)`
B. `4.5 xx10^(6)`
C. `1.8xx10^(6)`
D. `13.5 xx10^(6)`

Answer

A

Explanation

Here both spheres are connected in parallel so its effective capacitance, `C_(1)+C_(2)=(R_(1)+R_(2))/(K)`
`:.` Common potential of the connection
`V =(q_(1)+q_(2))/(C_(1)+C_(2))`
`:. V = (150xx10^(-6)+150xx10^(-6))/((R_(1)+R_(2))/(k))`
`:. V= (3xx10^(-4)xxk)/(R_(1)+R_(2))`
`:. V =(3xx10^(-4) xx9 xx10^(9))/(3xx10^(-1))`
`:. V = 9 xx10^(6) V `