Recent content by anban

Clarification about a conductor as an equipotential... Homework Statement This is not a specific problem, but a general question I have. In Griffiths 2.5 (pg. 97 for Third Edition), it states that "A conductor is an equipotential. For if a and b are any two points within (or at the...

Homework Statement I do not have a specific question, I am just wondering how one would go about finding the capacitance of three concentric spherical shells. Suppose the outer radius of the each shell is a, b, and c from the center outwards. Homework Equations E= -gradV C = Q/ V...

I'm not sure that I understand-- does δ(x-a) ≠ 0 when x=a? The way I am thinking about this now is that x-a is some coordinate point along a line?

Homework Statement For a function ρ(x,y,z) = cδ(x-a), give the meaning of the situation and describe each variable. Homework Equations As far as units go, I know that: ρ(x,y,z) = charge density = C/ m^3 δ(x-a) = 1/m and if those two are correct, then b must have units of (C/m^2)...

Homework Statement A pendulum length l is suspended inside a railroad car. The railroad car is oscillating so that its suspension has position xs = A cos (ωt) and ys= 0. Use the angle \varphi as the generalized coordinate and write down the equations that give the Cartesian coordinates of the...

Another clarification-- the D in the denominator is squared. Does that mean I need to take the square root of my result?

Typo, thank you! Big help! Turns out I was off by a decimal point. My answer makes a lot more sense now. Thank you very, very much.

Homework Statement I have a wire of some resistance, resistivity, and length. What is the maximum error in measuring the diameter that you can have if the resistance is to have 1% uncertainty? Homework Equations R = \frac{ρ*l}{\pi*r^{2}} for which I substituted the area as \pi(.5...

Homework Statement How do I find the electric field at a point above the center of a charged sphere? Assume the sphere is a shell.Homework EquationsThe Attempt at a Solution\ I know there will only be a z component to the electric field, because x and y components will cancel by symmetry. I...

Good catch: The expression should be E = 2\pikσ(1-\frac{z}{\sqrt{z^{2}+R^{2}}}). So, the denominator of the last term can be rewritten as z\sqrt{1-(R^{2}/z^{2})}. After a binomial expansion, I got that the E field decreases as 1/z.

Homework Statement Hi, I have a problem that describes a uniformly charged disk and the electric field a distance z from the center. I have found an equation that describes the E field at any point z already. Now I have to find out how the E field decreases as z increases-- as 1/r^2...

Got it- equal and opposite forces. Thank you.

Homework Statement I have a problem as follows: "Two charges of identical mass hang from the same point by a thread of length l. One has charge q and the other has charge 2q. Find the angle each mass makes with the vertical." Now, I got an answer and found that each mass will make the...

One more idea for solving this: If I simplify the the inner charged cube to just be a point charge surrounded by a cubical Gaussian surface, then computing the E field is very difficult. It is not simple because the electric field vector coming from the charge is often at an angle to the area...

Homework Statement Suppose there is a uniformly charged cube with known side length. I then imagine a larger, closed cube surface surrounding it. This larger cube has double the side length and is symmetrical to the smaller cube. Is is practical to use this Gaussian surface to compute the...