Gauss's law, cylinder of length L

lidl

http://img404.imageshack.us/img404/4148/gauss3j.png (infinitly long)

[latex]\Phi=\Phi_{0}(1-{r \over R}) {C \over m^2}[/latex]

What's the charge of the cylinder of length L?

Again, almost everything was wrong...

lidl

anyone? :(

lidl

Here's link to my paper: http://img202.imageshack.us/img202/5889/physics.jpg

JaWiB

You need to be much clearer in the problem statement and your work.

Is the cylinder hollow? What do r, R, [tex]\Phi[/tex], and [tex]\Phi_0[/tex] represent?

Also, it's probably OK to write notes in your homework like "the electric field points radially outward so the flux through the top and bottom of the gaussian cylinder is zero" rather than relying on vague drawings

lidl

This is from the test, as you can see, and everything I knew was written down...

lidl

please delete this post

lidl

ok, now I got the following:

Q=integral of /rho(1-r/R) times rdr d/phi dl

Which is the answer for the question of what's the charge of the cylinder L.

How to calculate it?