A spherical conductor has a radius of 14.0 cm and charge of 26.0 µC. Calculate the electric field and the electric potential (a) r = 10.0 cm, (b) r = 20.0 cm, and (c) r = 14.0 cm from the center.

Question

how do i calculate k?

Answer 1

k is the Coulomb's-law constant, which appears in the formula you need to use, you look it up. It is a constant of nature.

(a) there is no E-field indide the conductor. The potential there is the value at the surface, which equals
-kQ/R
where R is the sphere radius, 0.14 m, and Q is the charge on the sphere.

(b) and (c): Your turn