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Physicists Turn Pull Into Push
sciencehabit writes "It's textbook physics: An electric charge near the surface of a material gets pulled toward the surface. However, if the charge is spread out into the right shape and moves fast enough, that attraction becomes a repulsion, one physicist calculates. The odd finding could help physicists avoid unexpected effects when guiding beams of particles such as electrons."
Make it so!
They seem to have that repulsion charge with girls.
It's textbook physics: An electric charge near the surface of a material gets pulled toward the surface. However, if the charge is spread out into the right shape and moves fast enough, that attraction becomes a repulsion, one physicist calculates.
This finally explains so much about women's behaviour towards me.
== Jez ==
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we already know lots of ways to push things... jet engines to push planes, gunpowder to push bullets out of a gun, etc.
What we need is a way to PULL things, so we can make a tractor beam. So far we got... nothing.
It isn't like an ion engine at all. What they are saying is that electrostatic induction is not always attractive but it takes very specific conditions to make it repulsive. An ion engine doesn't use induction. Induction is the force between a neutrally charged object and a charged object.
Nothing in the article violates the laws of physics. It's merely a question of who did the math more accurately for the specific case of the given arrangement of electrons.
Cherenkov radiation is a well understood phenomenon. What you are missing is that the cosmic speed limit is the speed of light in a vacuum. Where the speed of light is slower (i.e. glass), it does not violate the laws of physics for a particle to move faster than that speed. In the given example: the electrons move faster in glass than light moves in glass, but still slower than light moves in a vacuum.
Nope, they're referring to Cerenkov radiation, it's a known effect and produces a very pretty blue light in nuclear reactors. It occurs when the phase velocity travels faster than the speed of light in that medium which is all fine and dandy and breaks no rules at all.
Please consider this account deleted, I just can't be bothered with the spam anymore.
For Cherenkov Radioation , doesn't the charged particle have to move through a dialectic medium, not above its surface?
I don't think the charges use spirit guides to exchange logical arguments to resolve disagreements.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
Not in the least. I've been in the 'core' of a couple of small research-grade swimming pool reactors (including this one), and you can see the blue light quite well and with no danger from radiation.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.