How Is Electric Flux Calculated for a Charged Sphere?

[22steve]

Homework Statement

A uniformly charged conducting sphere of 1.6 m diameter has a surface charge density of 8.0 µC/m2. What is the net charge of the sphere, and what is the total electric flux leaving the surface of the sphere?

Homework Equations

surface charge density = q/A
flux = E x A
flux = charge enclosed/ permittivity constant (Epsilon-naught)

The Attempt at a Solution

q = surface charge density x A
so (8e-12)x(4xpix 0.8^2) = 6.434e-11
then E = k(q/r^2) = .90377 = E
so flux = E x A = .90377x 4x pi x .8^2

 

[Doc Al]

The Attempt at a Solution

q = surface charge density x A
so (8e-12)x(4xpix 0.8^2) = 6.434e-11

Careful: μC = 10^-6C.

then E = k(q/r^2) = .90377 = E
so flux = E x A = .90377x 4x pi x .8^2

That's too much work. Once you find the correct charge, just use Gauss's law to find the flux. (But your method would work also. )