Recent content by Gaupp

Okay I got it on my own. Using the %difference = (E_infinite - E)/(E_infinite) Since E = n/epsilon_0 * (1-((.5a)/(sqrt((.5a)^2 + R^2)))) approaces n/epsilon_0 as R/a approaches infinity you can plug in n/epsilon_0 for E_infinite and the original equation for E. Solving this for %difference...

So now I have: Sorry this is going to be messy... R/a = sqrt(.25*((1-((epsilon_0*E)/n))^-2)-.25) = .99(n/(epsilon_0)) How do I deal with the E? If I sub in the other equation won't that just negate everything? I'm also asked to give the answer to two significant digits, but I don't see...

Homework Statement Consider two thin disks, of negligible thickness, of radius R oriented perpendicular to the x-axis such that the x-axis runs through the center of each disk. The disk centered at x=0 has positive charge density n, and the disk centered at x=a has negative charge...

q=e(#protons-#electrons). Ok I see now. The difference between the #protons and the #electrons would be the number of electrons lost or gained. I kept solving for just the number of electrons, by moving around the #protons in the equation. DOH! Thanks for the help there learningphysics.

How much does each ball weigh in your problem? It could be different, especially if you're doing this in MP.

.025 kg x 1000g x 1mol x 6.023*10^23 atoms in a mol x 13 electrons = #electrons 1kg 26.982g 1 mol 1 atom Al

I'm having difficulty with a problem on MasteringPhysics (such wonderful software...) and as a last resort I'm posting on here. This is, I'm sure, a really simple problem but I'm getting no kind of feedback from MP and there isn't an example problem like this in the book. Homework Statement...

Ok. Yeah I typed that in wrong. It should be 1*10^4 N. Thanks.

Oops. I think I posted this in the wrong forum. Can a mod or someone move this for me please?

I'm having difficulty with a problem on MasteringPhysics (such wonderful software...) and as a last resort I'm posting on here. This is, I'm sure, a really simple problem but I'm getting no kind of feedback from MP and there isn't an example problem like this in the book. The Problem Two...