Magnetic fields ain't like a hammer hitting a nail since the hammer does work.
Magnetic fields are like the normal force on a ramp. It doesn't do any work since it's perpendicular to the displacement.
I said that a magnetic field can't SPEED UP electrons and I stand by that. It can deflect them of course.
The fact is that the force that a magnetic field exerts on an electron is always perpendicular to the trajectory (same as a satellite in a circular trajectory in a central force field) so...
to krab:
I finally found out what's the problem. The formulas you wrote for the energy and work are mechanical work. You still need to add the energy of the electric currents. If you do that then you'll get zero work. This is in one of Feynman's lectures, chapter 13 I think.
I'm kind of busy...
The fact is that no magnetic monopoles have been ever found (like a point particle being the source of a magnetic field). If there were any magnetic monopole it would explain why is charge quantized.
More info:
http://budoe.bu.edu/~corth/monopole_faq.html [Broken]
I think you should be familiar with at least some Calculus before trying to get into Complex Analysis. I don't know if you are by the way, I ain't familiar with european education
Hi
I have no problem with the above, except that as far as I know \vec{N}=\vec{m}\times\vec{B} comes from the Biot-Savart Law as shown by Jackson's book on page 150.
Furthermore, a magnetic moment is defined for a current distribution J (Jackson p.146)
What causes me trouble is that I'm...
If it's like using an oscilloscope, then you have to count how many divisions are in a single period, and with that you can calculte the freq. as well
For the amplitude count how many divisions in the y axis does the waveform have
You're correct, furthermore, we Engineers and Mathematicians are focused on different things, even when studying the same topic. Generally speaking, the engineer ain't that interested in the theory, he just wants to know how to solve something, with the mathematicians is the other way around...
If it helps, the LT of the error function \frac{2}{\pi^{\frac{1}{2}} }\int_0^t e^{-u^2} du is \frac {1}{s(s+1)^{1/2}}
And since you can always work with the N(0,1) distribution instead of the more general N(m, sigma^2) I think you'll find the aforementioned result useful. If you need the...
Hi singleton. I've used both Maple and Mathematica (althoug not Calculus Wiz) and I would say that at the calculus level there isn't much difference.
Say, you need to check the derivative of something, and the integral of some other function? Both will do the trick.
In Mathematica (the...
It depends on the voltage (current ) source connected to the circuit.
Let's say you plug a 1 A source to the entire circuit
I found out solving for the entire thing that the current trough the resistor of 6R is 1/34 R
I wrote KVL for each mini loop, and then wrote KCL at the top, at...
My personal experience is that it depends on one's personal abilities (Aside from departments, schools, universities).
In Engineering they give you more [home]work, so you're stuck doing lots of stuff, some boring, some fun. The material ain't hard to understand. It's also important to be...
Hi, I would like to know how is the life of a graduate student, specially for PhD students, so I would really appreciate if someone could answer the following:
What are your sources of income?
If you have a fellowship/RA/TA, does your income cover for your expenses?
If so, what is the...
I hate "hand waving" answers but here I go:
In a capacitor you have a voltage because there are minus charges on one plate and plus on the other. On AC, you switch the polarity so the minus charges flow to the other plate over and over again.
If you make the switching very fast, then the...
Sorry, I meant gravitational force, I was thinking of something else.
And the fact that velocity ain't constant means that there is a tangentical acceleration as well, so you have to take that into account in Newton's 2nd Law.