Question

Can somebody expain why my ander wrong?
A spherical conductor of radius 10.0 cm has net charge
Q = 0.78 µC.
Calculate the electric potential at the following distance from its center, assuming the electric potential goes to zero at an infinite distance from the sphere. At 2.7 cm
I use this UE=KQ/r
[8.99*10^9)(.78*10^-6)]/.027=258754V

Answer 1

Isn't the distance from the center .12 meters?

Answer 2

If you really mean inside the conducting sphere the E field is zero and therefore V is the same as outside on the surface which is the same as the V of a centered point charge at that sphere radius.