Recent content by Shinobii

Where are you people getting these numbers from!? Look online at any university, they post the wages for professors. Assistant professors make >80k minimum (in Canada).

If anyone is keeping track, it turns out I should have been taking the derivative w.r.t x. . . f'(x_o) = \frac{d}{dx}f(x_o) . Woops!

I suppose when calculating the field angular momentum, we do not need to split the r < R integral \int_0^R . I also understand now that we are integrating over all space or over the entire field.

Hi! I would not worry about the extra year if you plan on doing graduate studies. Personally I would just get into graduate studies and teach myself the subjects. That said, you may want to boost your GPA if you plan on getting awards. However, most schools will only look at the final 60 credits...

This is true, solid state is a 3-4 year split with chemistry and physics at my university. You must have taken some QM if you wish to get an understanding of the subject.

Yep, sounds about standard! Good luck!

Ah, I think I figured it out. We are looking at the case where f(x_o) = 0 , so we just divide by v.

Also for the integration, would I integrate the r < R case from \int_0^R = \int_0^r + \int_r^R and the case of r > R, \int_R^{\infty} ? Or would I simply just integrate \int_0^R for both cases, without splitting the integral.

Homework Statement Calculate \phi_{ret} for a charge moving with constant v, along the x-axis. 2. The attempt at a solution $$ \phi = q \int_{-\infty}^{\infty} \frac{\delta(x' - vt')}{|\vec{r} - \vec{r}'|} dx'. $$ I then use the Dirac delta relation, $$ \int_{-\infty}^{\infty}...

The \phi has essentially absorbed the Sine term. It is just another way to rewrite the more general solution (Which involves both Cosine + Sine functions). The exponential comes from the solution to the differential equations. If you understand the differential equation, everything will make...

The angular momentum of the electromagnetic field is defined as, $$ \vec{L_{em}} = \int \vec{l_{em}} d^3r. $$ To solve this for a rotating sphere I must consider the cases where r < R and r > R. When I did this problem I thought that there would be two solutions, one for both cases; however...

Think about what the light will do. There is not much else I can do to explain. Draw the lenses and the ray diagrams without the pencil there, then add a pencil. As for ray diagrams, google it and view some of the images that pop up. Better yet, just think about it first. I mean, you should get...

We are simply looking the Real motion (i.e. no imaginary portion). The \phi is due to some phase. See Wikipedia for more detailed info! Or here is a great link: http://hyperphysics.phy-astr.gsu.edu/hbase/oscda.html

Have you attempted to do anything? What are you asking? Just do what the problem says! Draw the picture!

Ah I see now, I was going about it the wrong way it seems! Thank you very much @vanhees71 for the detailed solution, this clears up a lot of questions I had. Also, (just in case you want to edit your post) you should have u = \cos(\theta') . And you missed a / on your itex command (or an itex...