What is the electric field at the center (in N/C)?

[NegaChin]

A total of eight tiny conducting spheres, each carrying a charge of -110 nC, are placed one each at the corners of a cube 1.2 m on a side. Find the potential at the center (in V).

What is the electric field at the center (in N/C)?

 

[pam]

Just add up the eight potentials.
Use symmetry for E.

 

[NegaChin]

I understand, but how do I find the potential to begin with?

 

[jae05]

$$V=\frac{q}{4\pi\epsilon_0r}$$

 

[NegaChin]

Just a Clarification

should leave the q as neg. and nC or convert to C and make positive?;