Recent content by nickjer

Use: d = \frac{2\pi}{\left|\vec{G}\right|} Where \vec{G} is just the shortest reciprocal lattice vector orthogonal to that plane. I suggest first finding the three reciprocal primitive vectors. And then construct the shortest reciprocal lattice vector orthogonal to the (1,1,1) planes from those.

It says s\leq R. The loop that you draw is inside the wire, so you get a fraction of the total current. That fraction being the fraction of area of your loop compared to the total area of the wire. Outside the wire, you would just set s=R and get back the total current you were talking about.

Yep.

Use the relation: \frac{d}{dt}\hat{\boldsymbol{u}} = \boldsymbol{\Omega \times \hat{u}} I will do the first term for the derivative of the velocity (use the product rule): \frac{d}{dt}\boldsymbol{v_r} = \frac{d}{dt}v(t)\hat{\boldsymbol{r}} = \frac{dv(t)}{dt}\hat{\boldsymbol{r}} + v(t)...

First order perturbation is just an integral over the perturbing potential: E_n^{(1)}=\langle n^{(0)}|V|n^{(0)} \rangle So just integrate over that potential with the ground state wavefunctions for a simple harmonic oscillator. No need for Taylor series.

You do the exact same thing you do for a single harmonic oscillator, but now there are N oscillators. Knowing that E = E1+E2+...+EN and e^{A+B}=e^A e^B, you can solve this problem very similarly to a single oscillator. I suggest first writing out the partition function, and you will get more...

Have you thought about using perturbation theory? I am guessing V_0 is small since you mention it is a perturbative potential. So are you supposed to find the ground state to first order in V_0? Or 2nd order?

The dispersion isn't quadratic so there is no classical kinetic energy term. I am guessing that you are giving the dispersion for an electron in a crystal. Since you are lacking in details.

My guess is yes. It makes little sense to just calculate the phase velocity for a single frequency.

What is the net charge of the inner surface (assuming you already solved it, you are sorely lacking details)? Then what does this make the net charge inside of the outer surface? Then, using Gauss's law, what should the charge distribution on the surface be? Hopefully you understand my line of...

Here you go. I believe this is what you want: http://en.wikipedia.org/wiki/Term_symbol

The first and second order spectrum has to do with the 'm' in the diffraction grating equation. I have no idea what happened to your 'm' on the left. The equation is: m\lambda = d \sin(\theta_m)

Does it say if it is an intrinsic semiconductor or is it assumed? Also, can we see some work.

I suggest looking up the equation. It is very easy to find. Just google "intrinsic carrier density". Good luck.

I thought the inertial reference frame was outside the car and not inside the car since that frame was accelerating. I only ask because you also say "I am assuming that the best way to solve this problem is to use a classic Newton's 2nd Law analysis using an inertial reference frame that is...