Question

A solid conducting sphere with radius R = 0.390 m carries a net charge of +0.650 nC.

Answer 1

Answer:

38.5 N/C

Explanation:

The electric field generated by a charged sphere at a point outside the sphere is equivalent to the electric field generated by a single point charge, and it is given by

$E=k\frac{Q}{r^2}$

where

$k=9\cdot 10^9 Nm^2C^{-2}$ is the Coulomb's constant

Q is the net charge

r is the distance from the centre of the sphere

In this problem, we have

$Q=+0.650 nC=0.65\cdot 10^{-9}C$

$r=0.390 m$

Substituting into the equation, we find

$E=(9\cdot 10^9)\frac{(0.65\cdot 10^{-9}C)}{(0.390m)^2}=38.5 N/C$