Two conducting spheres of radii r1 and r2 are equally charged.The ratio of their potential is?
Both the spheres have the same surface charge densities.
Let us suppose that the sphere with radius R1 has a charge q1 on it, and that the sphere with radius R2 has a charge q2 on it.
Now,
q1/[4π(R1)²] = q2/[4π(R2)²]
=> q1/R1² = q2/R2² => q1/q2 = (R1/R2)²
Potential in first sphere = V1 = kq1/R1
Potential on second sphere = V2 = kq2/R2
Thus, V1/V2 = q1.R2/q2.R1
= (q1/q2).(R2/R1)
=(R2/R1).