# Klaynos

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## Posts posted by Klaynos

### Smashing atoms

From an efficiency standpoint' date=' the best we can do is matter/antimatter annihilation, which converts 100% of the mass. Proton/antiproton annihilation would convert almost 2 GeV per reaction.

Now, I admit getting ahold of a pile of antiprotons is a bit of an obstacle...[/quote']

Oh yeah annihillation sliped my mind for a moment *sigh* too early in the afternoon for this thinking business....

### Smashing atoms

It is VERY VERY difficult to convert all of an atoms mass energy to other forms of energy, the best we can do is fusion reactions which is a few tens of MeV, which is obiviousey 10000000 times stronger than a chemical reaction but still not earth destruction power.

Anyone can work out the total energy of a stationary atom using:

E=m0c^2

For a moving particle you have to take relativistic effects into account

E=(gamma) m0 c^2

Where gamma is 1/(1-(v/c)^2)

Mass (m0) in kilograms, c = 3*10^8ms^-1, and v in ms^-1

Work it out with an electron moving at 0.9c ms^-1...

I read alot but only post very infrequently, I tend to only post when I actually have something constructive to say and actually think through what I've written before actually hitting post.

That way I end up writeing alot of posts and then deleteing them, hence I'm NOT addicted

### Science Project Help

I'm afraid I don't know any normal magnet formulae for repulcive forces, never even come accross any, if noone get's back to you I'll try and have a look about and quiz my friends tomorrow afternoon, sorry I can't investigate now got an exam in the morning

### Science Project Help

As 5614 said about the violentness of stoping suddenly I thought I'd just quantify that a bit.

Impulse = new momentul - original momentum = Force * change in time

(Force=rate of change of momentum)

This can also be written as

Impulse = intergral between t1 and t2 of the sum of F dt

Although that is superfluse for your understanging of it.

So going back to Impulse = new momentul - original momentum = Force * change in time, the momentul change is constant due to the conservation of momentum, so if the time is decreased to maintain this conservation law the force has to get considerably bigger.

This is why cars have crumple zones.

### graphcalc

Has anyone ever used graphcalc, or any other open source graphical calculator for windows or linux, if so what did you think of it?

Cheers

### i know everything

heisenberg's uncertainty principle time!

so' date=' tell me the velocity of an electron in any atom of silicon in any transistor in your computer at any moment in time and its direction at this same instant in time. make sure you tell me which specific atom this is and what instant in time you are making your recordings in[/quote']

You know as soon as I started reading the thread the words "uncertainty principle" jumped streight into my mind, always ask a question that we don't know the answer too.

How does gravity work, and specifically what aspect of this creates the confussed motion of pendulums during a solar eclipse.

(If we suppose for the time being that the motion observed is actually a proper physical phenomena that actually exists.)

my opinion is pretty much "if you predict enought stuff to happen over enough time, and you're quite vague about it, you have to be right sometimes"

### Can Heisenberg's principle ever be overuled

of course their is always the option we are completely wrong and that everything which has been said before is completely incorrect then the uncertainty priciple can be ignorened, but as stated above as far as we know,

uncertainty in momentum * uncertainty in position = planks const / (4 pi)

Is the BEST we can ever achieve...

### Is this an error?

My understanding of this is that it is meant to say positron, and I would read it as such, else there is not conservation of mass-energy.

### The Official "Introduce Yourself" Thread

Hello, I'm Klaynos or Ed, I'm a physics student from the UK, you'll probably see me on IRC...

### Scramjet screams into history at 7,000mph

To be fair a plane which dives into the sea is not really much use' date='

British Dont drink larger. I have told you this before. We drink BEER! only chavs drink larger......[/quote']

Depends who's on the plane...

Some non-chavs drink larger, just not cheap larger...

### The Situation

My university (I'm from the UK) has just announced it is closing several departments including Chemistry, this does not effect me (Physics is a seperate school) but what do you think of universities which do this?

### True vacuum?

Any point in space is constantly having pairs of particles create and self anihilate each other.

I think the proof of this is using the uncertainty priciple of

(D is delta)

DEDt~h/4pi (Delta Energy * Delta Time aproximately = Planks Contant divided by 4 pi (h bar/2))

Then for a small enough amount of time any point in space can and will have Energy "borowed" from the universe to the amount of h/4pDt, which as E=mc^2 then creates a particle and anti particle (Mass-Energy), these then imediately self anihilate so preserving conservation of Energy. But it has happened and happens again and again meaning that vacuumes are VERY active indeed.

The second part of your post, I was thinking the other day that if we wish to time travel the secret is not moving us from here to there, but moving someone from the future or past to now, in an attempt to preserve energy (and mass as mass is a form of energy), we would have to push energy into the original time...

### Vacuum temperture

This happened on IRC:

[19:11] <Jordan14> i posted in on the forum but is there a temperture in a vacuum

[19:11] <RICHARDBATTY> should be near absolute zero

[19:12] *** Jordan14 Quit (Quit: Jordan14)

[19:12] <Klaynos> dedends, yes there is, but only because we can't create a proper vacuum, if we could create a proper vacumm, ignoring the uncertainty principle, there could be no atoms, therefore no kinetic energy/internal energy, therefore no temperature

[19:12] <Tesseract> no

[19:13] <RICHARDBATTY> no energy or method of condution in a perfect vacum

[19:13] <Klaynos> no such thing as a perfect vacuum that we can create though :s

[19:13] <RICHARDBATTY> true

[19:13] <Klaynos> and even in vacumm there is constant creation and descrtuction of subatomic particles :S

[19:13] <RICHARDBATTY> quantum yes

[19:14] <RICHARDBATTY> agreed:)

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