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Comment Researchers found phase transition of H2O at 0 C (Score 2) 145

Researchers found out that H2O, commonly known as "Water", surprisingly undergoes a phase transition at zero degrees Celsius under normal atmospheric pressure.

The paper is still under review, but our experimental studies on 594 samples of the substance found that liquid H2O becomes solid when cooled below this temperature. The presence of the solid state was confirmed by probing (poking) the substance with a sophisticated testing device (finger).

By testing with different temperature ranges, including randomized temperatures, it was confirmed that the transition happens at or close to zero degrees Celsius.

Comment Re:Question for the Physicists. (Score 1) 79

A magnet exerts force e.g. on another magnet. But exerting force doesn't require energy as long as nothing moves. Work (W) is force (F) times distance (s) (in direction of the force) W=F*s, so as long as s=0 no work is done, no Energy needed.

Imagine the magnetic attraction replaced by a (extended) spring between the two metal parts. As long as nothing moves no energy needs to be replenished in the spring. If the metal parts are allowed to move closer energy is transferred from the spring to those parts (or whatever holds them apart), to "replenish" the energy you need to pull the parts apart again. To get back to the starting configuration you need to put back in as much work as the magnets released previously (here i simplified the magnets somewhat: they shouldn't magnetize/demagnetize each other or any material, there'd be effects like hysteresis and you need to put some additional work in and get some heat out).

As to where the energy is "stored": it is in the magnetic field. When the magnets move closer together the magnetic field is in an altered configuration that requires less energy. The difference goes into the work W=F*s.

Comment It was staff at Gallaudet University who sued (Score 1) 337


Gallaudet University is a school for the deaf. They (Glenn Lockhart and Stacy Nowak) wanted to use the content for their coursework, but couldn't use it as is, so instead of providing closed captioning themselves or work something out for the specific material they were interested in they decided to sue Berkeley.

Sadly this is not made clear in the submissions to slashdot, so speculations run amok about ambulance chasing attorneys and some deaf students suing.

I hope Glenn and Stacy are happy with their result.

Comment Re:And thus... (Score 1) 141

It seems to be easier and faster to switch the battery, load it in sufficient time, and switch it into another car ...

Of course there are some things that need to be adressed (who "owns" the battery, standardisation and safety issues), but if it's technically doable the finance folks and lawyers usually come up with a design to cover the rest.

Comment This is complete nonsense (Score 1) 277

Aparently it's about this article: http://www.lpi.usra.edu/meetings/abscicon2010/pdf/5469.pdf

1) Producing the desired magnetic field with the proposed wire-loop can't work, you can probably get a few gigawatt from Maxwell rotating in his grave in result of that paper.

2) The electric current in the wireloop is aparently driven by a static electric field, ever hear about static electric fields being conservative?

3) Somehow electric current is generated by catching electrons, but where do they leave the System?

4) Where does the energy come from to separate electrons and protons from the plasma? To put some spatial distance between positive and negative charge you need energy.

5) A sail of 8.400 km with (square or what?) shall produce 10^27 W of energy. That means over a 4-Billionth (1/4*10^9) of the solid angle of the sun it produces 2.5 times the total energy output of the sun. Surrounding the sun completely with these contraptions should yield 10^10 times the total energy production of the sun.

This paper can't even stand up to basic highschool-physics.

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