Maxwell's Equations

[Aizzat]

hopefully it does make sense to people? yeah it really does make sense now. thanks dood

[closnclos]

yes you tube makes it simple Thanx

[jonathanaguire]

see....our school lectures really need to use youtube. show this for the entire class and then go into your own explanation. hell....alot of what we learn during lecture can be learned on youtube....

[BeingOfLight111]

thankyou soo much

[mehdital]

i think its a Nabla not a Delta!!

[floopsie666]

@mehdital He didn't say delta. He is saying del dot e. The del is usually used for operations involving vector fields (gradient, divergence, curl) and the dot is the dot product

[mehdital]

@floopsie666 ah ok , but here in europe we use the name Nabla not Del

[broomhandlecowboy]

Yes it did make sense - thank you

[jimmyshitbags]

hmm i never thought of it in that way, light has a constant speed in all frames because space is going to have the same permeability and permittivity regardless of the observer's motion?

cool.

[msf60khz]

How do the equations tell us that the magnetic and electric fields of a wave are in phase, whereas in the case of induction they are in quadrature?

[independence8]

first time its hard...second time its hard....8th time and it gets easier...now its very easy hehe

[DanFrederiksen]

nice try. I understand a lot of it but haven't been introduced to the inverse triangle notation. perhaps you could explain that?

maybe wth a geometric example if applicable.

so it's not just an explanation to those who already know the material...

I'm just saying :)

[VDubSlug]

Oh, and del-dot-F = dF/dx+dF/dy +dF/dz

[DanFrederiksen]

and I'm not well versed in differential math either :) does it mean a gradient? the ramp of F with regards to the 3 spatial coordinates? so del.E of let's say a point charge like an electron in free space would be vectors radially away from the electron? is that it?

[VDubSlug]

*exactly* (it can be hard to picture in 3-space)...we start with point sources like an electron, then go to shapes, then add in magnets, *then* put in changing charges, fields...

[DanFrederiksen]

I'm smart : )

[DanFrederiksen]

well, as I think about it a bit more, I don't get it at all :) what I described as understanding of del.E was what is called a vector field? but on the right hand side of the first equation is only P over e0. is P some default vector field thing or is del.E not a vector field at all?

[VDubSlug]

delE is a vector field (strength and direction of the electric field; del dot E is a scalar field that just shows the value of the field, not the direction. (think of a ball rolling down a hill [point source])

[DanFrederiksen]

ok but even as the slightly simpler scalar field, how does that jive with the right hand side of the equation. what is P that is can be proportional to an arbitrary E scalar field?

[VDubSlug]

(it's a rho, signifying charge); the higher the charge, the higher the E scalar field

[DanFrederiksen]

you're not getting the problem. is rho a scalar? how can a scalar be equal to a scalar field..

[Inachos]

rho is the charge density and generally depends on the coordinates, so in the general case rho is a skalar funktion, just as del dot E

[independence8]

del is a partial differential operator

[TheOriginalGilla]

Hey :)... I understand what permittivity is but could you explaun what permutation is? ... Not sure if i spelt it right btw..

[VDubSlug]

In the same way that q charge makes so much E due to the permitivity of free space then the permeability is the same thing for magnets (how tightly the filed lines are curved near the magnetic pair)

Oh, and permutation is how many ways you can arrange the members of a set a set...the permutations of ABC are" ABC, ACB, BAC, BCA, CAB and CBA.

[TheOriginalGilla]

Cool... Thanks so much!! (:

[Zookhaarh]

I wish there was an animation or smg : (

[hazyboi13]

Im in love wit physics too....damn!

[VDubSlug]

Physics was my first love...three other degrees later, I still find myself reading articles about the LHC, orbital theory.

We never said goodbye, and I hope we ever do.

[Clayjrjr2]

It might help people understand better if there were less "uhms" and "uhs". I like your explaination though. I don't know what permeability or the other P word you used is... and why you use them... what they are and mean... it would help alot. thanx.

[VDubSlug]

In the material I have an MS or PHD in, we get fewer uhs. This, I haven't studied physics since 1987. As it turns out (as one of my students pointed out last year), the uhs give them more time to take notes *shrugs*

[lolhowdoishotweblol]

not bad not bad

i enjoyed your explanations. i fail if i ever try to teach

[VDubSlug]

Thank you...it's always been my dream, and now I'm living it.

[eldominicanboy]

man, I just love physics. Nice video, very straight foward

[VDubSlug]

Sorry for the long delay---Physics was my First Love

[VDubSlug]

That is correct. Think of the dot product as a hill (that would be 2-D, but still)...the dot product is the slope at a point on that hill. And you're right about the cross product. Make an L with your index and middle finger, and your thumb is in the direction of the cross product. That work?

[glitterophelia]

I think my brain just exploded.

[meremonami]

math = booo in my head, but you are fun to watch, just don't think that any of the words went into my head.

[VDubSlug]

They *had* to go into your head, because you heard 'em...but they didn't go to the Understanding part of your brain, but would up somewhere else...any Ideas what part of your brain it stimulated?

[meremonami]

the part that made me pay attention to everything except trying to understand the foreign language you were speaking?

[VDubSlug]

There's a certain amount of Greek in there...but honest...it's Physics English.

[aleterra]

English is not my first language but I think you English is good.

[thelaynie]

Wow. Just... my brain hurts now. Please tell me physics classes start out a bit... less intense? :D

I will say I understood the concepts, even if the equations broke my brain. And dude... geektalk... *drool*

[VDubSlug]

Well, it *did* come from a Junior/Senior class...

[thelaynie]

That does, in fact, reassure me. Why is physics so hot?

[VDubSlug]

Phycists are hot....physics is fascinating

[b1gdawg]

That was fascinating! Are you planning to do it in English?

-A2L