Electrostatics: Potential of +28.0 nC Sphere in Vacuum

[NegaChin]

A 2.00 mm diameter conducting sphere in vacuum is charged with +28.0 nC. Determine the potential at a distance of 1.70 m from its center. [Hint: Since 1.70 m >> 2.00 mm this is essentially a point-charge.]

 

[hage567]

Please show what you've tried so far.