swansont

Specifically' date=' raise the current. If you raise the voltage you will get higher energy in the continuum but not in any transition-specific values. If you want more intensity you need more electrons. [sub']edit: spelling[/sub]

I tend to agree - I don't have much use for the willfully ignorant.

I'm not sure what you mean by 50% density.

Photon momentum is E/c. The have no rest mass.

Your question depends on what you are trying to shield - there's the current of the lightning stroke, and the EM radiation that it gives off. You can obviously be protected from the current by a properly grounded lightning rod. In that sense the lightning is basically a DC signal as far as understanding the dynamics. But the short duration of the stroke and the acceleration of the charges means that EM radiation will be given off. You car isn't going to protect you against that, since radio waves obviously can penetrate inside.

Under what assumptions? Do you have a link for this?

[math]1/r^2[/math] is from a classical gravity equation. Electron size is quantum mechanics. Danger, danger, Will Robinson!

If you move the source away from the observer it will redshift. Also there are crystals in which you can do nonlinear optics and get frequency doubling (the direction it's usually done) but you can also get difference frequencies, and go to lower values. So yes, it's possible.

Dirac theory has the electron as a point particle; no structure. Every experiment of which I am aware that measures the size is consistent with zero. You can't state that a dimensionless particle will create a singularity until you have come up with a theory of quantum gravity.

And if we all walked into a bar, this would be in the "jokes" thread...

Two photons, in order to conserve momentum.

A gamma is a photon.

Note that the "vitriol" names likely came first, before much was known about the chemistry details.

Well, I've assumed the balloon was not made out of lead, or anything similar. But the original question strongly implied that thw whole system was less dense than air. Under those circumstances it will move toward the front. Or toward the inside, in bloodhound's case of circular motion.

And I don't disagree with that. But what I'm saying is that while situations such as "in the winter, it's dark yet we're still awake, so let's have sex" and my previous example are biologically driven, they are not physiologically driven. Women are able to conceive year-round. Men want sex basically all the time. We don't grow antlers and rut, and women show no special changes that signify they are in estrus that set us off (what signs are present are always present). It's all part of the reproductive strategy that we adopted. Nothing in that argument separates us from the rules of biology.

Citation, please.

Try the CRC Handbook of Chemistry and Physics.

That's a consequence of Newton's 3rd law. Action and reaction. But the earth's motion is only influenced by the force you exert on it, not the force it exerts on you. The fact that they are equal and opposite tells us momentum will be conserved in any interaction involving those two objects.

Atoms don't need an energy source to exist. There's no friction or anything similar at that level. An atom, in fact, has less energy than the constituent particles. Because there are attractive forces (nuclear for the nucleus, as was mentioned, and electromagnetic for the electrons) you can and do form a bound state, which requires the release of energy. Once you have formed that state there is no need to do anything else.

The air filled balloon will move back relative to the car. Newton's first law.

The size of the holes tells you what frequencies are shielded by the cage. Lightning is basically a DC signal, so you can have big holes - it becomes a circuit problem; what path gives low resistance to the current. If you expected your car to protect you from radio waves or higher frequencies, then you'd have to worry about holes. The idea here is similar to why radio telescopes can be made of mesh/honeycomb but visible telescope reflector "dishes" are mirrors.