Recent content by carlosbgois

Hey there. Your logic is valid, but you stopped one step shorter from the answer. Whathever internal forces exist in the solid, the net total (vector sum) is zero. The body behaves as a single total mass located at the body’s center of mass. You may check any classical dynamics textbook for a...

Your second suggestion, the one by Schumacher and Westmoreland, looks like exactly what I was looking for. Thank you! I am still interested in further suggestions, if anyone else would please.

Hey there! While considering going into foundational issues in QM (reading abou entanglement and Bell's theorems now), I realized I may need a better grasp of QM. I have studied both Griffiths' and Cohen-Tannoudji's (both volumes, excluding the appendices) books. I am not very confident in my...

Homework Statement z\frac{d^2z}{dw^2}+\left(\frac{dz}{dw}\right)^2+\frac{\left(2w^2-1\right)}{w^3}z\frac{dz}{dw}+\frac{z^2}{2w^4}=0 (a) Use z=\sqrt y to linearize the equation. (b) Use t=\frac{1}{w} to make singularities regular. (c) Solve the equation. (d) Is the last equation obtained a...

Member advised that the homework template is required. Hey there! Need help figuring this out: Find the real and imaginary parts of \frac{1-z}{i+z} What I've tried was to notice that z\bar{z}=|z|^2, thence...

Homework Statement [/B] Consider a hydrogen atom which, in t = 0, is in the state given by \psi(\mathbf{r},t>0)=\frac{A}{4\pi}R_{10}(r)+\frac{cos\alpha}{4\pi}\left(\frac{z-\sqrt{2}x}{r}\right)R_{21}(r) Expand ψ in terms of the {Φnlm} basis of normalized eigenfunctions...

Got it! Thank you all.

Hallsoflvy: I have used the definition by the integral \int f(x)\delta(x)=f(0) vela: with this substitution it worked. Thank you all for the help

Homework Statement [/B] Prove that \delta[a(x-x_1)]=\frac{1}{a}\delta(x-x_1) Homework Equations In my attempt I have used \delta(ax)=\frac{1}{a}\delta(x) but I'm not sure I'm allowed to use it in this proof. The Attempt at a Solution Some properties of Dirac delta function are proven using...

Homework Statement [/B] The total force on a moving charge q with velocity v is given by \mathbf{F}=q(\mathbf{E}+\mathbf{v}\times\mathbf{B}) Using the scalar and vector potentials, show that \mathbf{F}=q[-\nabla\phi-\frac{d\mathbf{A}}{dt}+\nabla(\mathbf{A}\cdot\mathbf{v})]Homework Equations...

Thank you for your answer. I was wondering this because of the following excerpt, from a textbook example on solving Helmholtz equation for a cylindrical cavity: "Once a solution (with Bz = 0) has been found for Ez , then the remaining components of B and E have definite values. For further...

Hey there, I have a quick question, and it can be answered with a reference to a book chapter of article. If I'm given the z component of the electric field inside a resonant cavity, and furthermore, if it's set that Bz = 0, how do I determine the other components for both E and B?

Yes I'm looking for a general solution: given θ, what is the arc length?

Sorry about that. Here is an image showing what is the arc length I'm referring to:

I've been trying to figure out the most straightforward way of doing this for a while, and would like to get some advice on new approaches, as the one I was using didn't work out at all. So here it is: The stadium billiard is defined as two semicircles joined by two tangent lines, as shown in...