Two metallic spheres of radii 1 cm and 3 cm are given charges of `-1 xx 10^(-2) C ` and `5 xx 10^(-2) C` , respectively . If these are connected by a conducting wire , the final charge on the bigger sphere is

Options

A. `2 xx 10^(-2) C`
B. `3 xx 10^(-2)C`
C. `4 xx 10^(-2)C`
D. `1 xx 10^(-2)C`

Answer

B

Explanation

Net charge on spheres `=q_(1) +q_(2)`
`=-1 xx 10^(-2) +5 xx 10^(-2)`
`=4 xx 10^(-2)C`
Charge carried by sphere `prop` Radius of sphere
`(q_(1))/(q_(2))= (r_(2))/(r_(1))`
`(q_(1))/(q_(2))=(3)/(1)`
`q_(1)+q_(2)=4` Charge stored by bigger sphere
`=(4 xx 10^(-2))/(4) xx 3 = 3 xx 10^(-2)C`