Electrostatic Potential of a Charged Metallic Shell

[newyorkcity]

Homework Statement

Given a charged metallic spherical shell of radius a=2.75cm, with a potential of 2.5kV a distance of r=6.0cm from the center of the shell, what is the charge on the shell? Calculate the potential on the surface of the shell.

Homework Equations

V=kQ/r

The Attempt at a Solution

I am assuming that I should just insert values into the equation, so...

2500V = (8.99E9)(Q)/(.060m)
Q = 1.7E-8

Is this calculation correct? I am not sure if the radius of the shell needs to be considered. Also, am I using the right units and are the units of Q Coulombs?

 

[ashishsinghal]

Calculation is correct! Radius will be considered in the second part of the question.