Among two discs A and B, first have radius 10 cm and charge `10^(_6) -mu`C and second have radius 30 cm and charge `10^(-5)`- C. When they are touched, charge on both `q_(A)` and` q_(B)` respectively will, be

Options

A. `q_(A)=2.75muC, q_(B)=3.15muC`
B. `q_(A)=1.09muC, q_(B)=1.53muC`
C. `q_(A)=q_(B)=5.5muC`
D. None of the above

Answer

D

Explanation

Let q be the charge transferred then
`(q_(1)+q)/(r_(1))=(q_(2)-q)/(r_(2))`