a charged spherical conductor has a surface density of 0 7 C/m2 when it's charge is increased by 0 - Physics - Electric Charges And Fields

Question

a charged spherical conductor has a surface density of 0 7 C/m2
when it's charge is increased by 0 44 C , the charge density
changes by 0 14 C/m2 find the radius of the sphere and initial
charge on it ?

Vara · Accepted Answer

Surface charge density:σ=QA  =Q4πR20
7=Q4πR2    (1)0 7+0 14=Q+0 444πR20 84=Q+0
444πR2   (2)(1) / (2):0 70 84=QQ+0 440
7Q+0 308=0 84Q0 14Q=0
308        Q=2
2 CFrom equation (1):0 7=Q4πR2R2=Q8 8R=2 28
8   =0 5 m

a charged spherical conductor has a surface density of 0.7 C/m2 .when it's charge is increased by 0.44 C , the charge density changes by 0.14 C/m2.find the radius of the sphere and initial charge on it ?