Question

a uniformly charged conducting sphere of diameter 1.2 meter has a surface charge density of 8.1 millimeter the electric flux

Answer 1

(a) The charge on the surface of the sphere is the product of the surface charge density σ and the surface area of the sphere (which is 4πr

2

, where r is the radius). Thus,

q=4πr2σ

=4π(21.2m)2(8.1×10−6C/m2)

=3.7×10−5C

(b) We choose a Gaussian surface in the form of a sphere, concentric with the conducting sphere and with a slightly larger radius. The flux is given by Gauss’s law:

ϕ=ϵ0q=

8.85×10−12C2/N.m23.66×10−5C

=4.1×106N.m2/C