Weird Facts of Physics: 1000s of Tons in a Teaspoon

[daveed]

J.J. thompson got a nobel prize for proving the electron a particle, and then his son wins one for proving it a wave
wierd coincidence

 

[what_are_electrons]

Try dropping a round magnet down through a square piece of aluminum tubing. You can watch it slowly, and I do mean slowly, go round and round as it goes down and down. For a two foot length it takes 8-10 seconds to drop from the top to the bottom.

 

[plover]

I heard once that if you took a bottle of water to Mars and poured it out, it would both freeze and boil and the same time!
(don't know if that's 100% true or not, but I found it pretty fascinating).

I'm not sure whether it's precisely true either, but it's very superficially plausible. Boiling temperature depends on pressure and the Martian atmosphere is extremely thin and thus has very low pressure. Freezing temperature also depends on pressure, but, at least in the range between the atmospheric pressures of Earth and Mars, I think it is usually (always?) a very small change compared to boiling temperature. IIRC, temperatures on Mars never reach the 0 C, though I think they do reach -20 C or so (somebody correct me here if I'm way off). One of the Martian polar ice caps is supposed to be mostly dry (CO₂) ice.

Anyway, in order to figure out what would really happen to water on Mars you'd have to know the temperature and pressure, what the equilibrium state of water is under those conditions, and some probably basic stuff about vapor pressure and such (that I haven't thought about recently enough to remember exactly how it works ).

 

[Alkatran]

Venus is the only planet that rotates clockwise.

That just made me laugh, because if you looked at it from the other side it would be rotating counter-clockwise. In fact, come to think of it, are there any planets not rotating in the same direction they go around the sun? (As in, the sun would never set, the north or south of the planet faces the sun)

 

[selfAdjoint]

You laughed too soon. Direction of rotation in the solar system is always stated relative to one side, which can be established by reference to the stars, specifically Polaris. This selected side is called "above".

 

[Alkatran]

You laughed too soon. Direction of rotation in the solar system is always stated relative to one side, which can be established by reference to the stars, specifically Polaris. This selected side is called "above".

My point was that it's a very arbitrary conclusion. It would make more sense to say only one planet is rotating in the direction opposite of ours. A similar example is that I've always tried to hold in mind that North is NOT up. North just happens to be what we define as the top of our planet. There's no reason why south isn't just as good a "top". (or... is there?)

Also, do you know what the inclinations of the planets' rotation is relative to their orbits? Is there some standard? Are most planets rotating around the sun on a certain plane? (See: any picture of the solar system in textbooks)

These are all things I've wondered about...

 

[chroot]

Any good encyclopedia will have all the data you want, Alkatran. www.wikipedia.org has all of it, for example.

- Warren

 

[Ivan Seeking]

For those who are far-sighted, in a pinch, any pinhole can act as a lens - including the little gap formed in a tightly curled index finger. This works for the same reason that a pinhole camera does. I had a professor who could only see to enter his locker combination this way when he returned from his jogging. His glasses were in the locker.

In fact, Integral, this was Dr. Fontana. He pointed this out one day before class.

 

[Ivan Seeking]

In Relativistic Electrodynamics, when one calculates the electric field vector of a negative charge q at time T-t, that moves with a constant velocity v as seen by P at time T, we find that the electric field vector points exactly to where the charge q will be at time T, in spite of the delayed propogation of the field from q. In other words, the vector points to where the charge really is at that moment, wrt P, in spite of the fact that what we see at P, at time T, was from q at time T-t. There is no immediate and obvious reason why this must be true.

Why must the Electric field vector point to where the charge really is at the moment that the field is measured? At first this seems to be an amazing coincidence that simply is true! However, we can create problems where, were this not true, we would find violations of the conservation laws. I believe this is demonstrated by considering a charge moving in a high velocity orbit around a strongly positively charged mass. I'm not sure what happens to our constant velocity demand here.

 

[Math Is Hard]

I'm not sure whether it's precisely true either, but it's very superficially plausible.

Thanks for weighing on that, plover. I picked up this tidbit from a planetarium show about a year ago and I didn't trust my memory to be accurate. But yes, he said the same thing you said about how the extremely low atmospheric pressure would result in a very low boiling point. He compared it to how water comes to a boil quicker when you're at a higher altitude, like up in the mountains.
Well, maybe our grandkids will one day settle this once and for all, huh?

 

[kjones000]

More odd physics things.

I consider this a fun fact: you could condense some interstellar molecular clouds into REALLY big martinis (sans olive or vermuth). (Ok, it might be a little toxic)

Mirrors would not work without quantum mechanics (assuming you could get light to work without QM).

Black holes could be considered boring. If you know the mass of a non rotating black hole, you can calculate almost all of its other attributes.

The state of a particle can be "coupled" to the state of another particle on the other side of the observable universe.

Einstein did not win his nobel prize for relativity.

There is a smallest possible unit of time, and we actually know how long it lasts.

Einstein's biggest mistake was not a mistake.

Lithium Beryllium Nitride is the only salt where the small ions will fit in the holes left by a close packed lattice of the larger ions. (I am considering lithium nitride and beryllium nitride to be degenerate cases of Lithium Beryllium nitride).

Photons take many centuries to work their way out from the center of the sun.

Diffraction gratings - nuff said.

When considering fission and fusion reactions, iron is by far the most stable element (lowest energy) but very very little of the universe made of iron.

Universes have a lot of similarities to black holes.

Some areas of math have zero application to any physical phenomena.

Some areas of math had zero application to any physical phenomena until a few bridges fell down.


Extremely bright people, capable of understanding extremely complex subjects can be incapable understanding what situations require consideration of anthropomorphic principles.

 

[Ivan Seeking]

In any solution to a physical problem that yields a complex solution, sometimes the imaginary part of a complex number has physical meaning, and sometimes it doesn't. Though the reasons for this are usually clear, this inconsistancy has always bothered me. I have often wondered if we might be missing something; somehow.

 

[Tachyon son]

I remember years ago when I first read the definition of a singularity: "a point with infinite density and which takes 0 space".

Im not physicist, not even smart considered, but I honestly think that is completely impossible for our brain to "understand" such singularity concept.
Our brain algorithyms and structure do not allow us to imagine that.

Not even the vacuum AFAIK takes 0 space!

Im not sure if I have expressed my idea properly... :blush:

 

[Gerinski]

A weird thing about hadrons (common subatomic particles such as the protons and neutrons making the nucleus of every atom) is that only a very very very small part of their mass is due to its constituent quarks. For example, a proton (made of 3 quarks uud) has much more mass than the sum of the masses of its quarks:

The mass of the 3 quarks is 0,003 + 0,003 + 0,006, yet the mass of the complete proton is 0,938 !

Most of the mass we observe comes from its kinetic and potential energy. These energies are converted into the mass of the hadron as described by Einstein's equation that relates energy and mass, E = mc2.

 

[Gerinski]

I'm thinking of another weird fact about the subatomic world, but I can't fully explain the details, I would like someone to say more about it:

The protons and neutrons making the nucleus of every atom, due to its confinement in such a small region of space, vibrate moving at incredibly high speeds, a substantial % of the speed of light.
As dictated by relativity theory, at such high velocities the rate of passage of time is much slower than it is for us.

So it's kind of paradoxical that we as a macroscopic chunk of matter age at our usual rate, while the particles we are made of are aging at a much slower rate ...

Could someone confirm, in our average lifespan of 70 years, how many years have passed to the protons and neutrons we are made of?

 

[ShawnD]

People put higher octane rating fuel in their car to prevent knocking, but true octane actually increases knocking (octane has an octane rating of -20).

 

[Einstienear]

I heard once that if you took a bottle of water to Mars and poured it out, it would both freeze and boil and the same time!
(don't know if that's 100% true or not, but I found it pretty fascinating).

Hmm, That could happen.

BUT, you must define BOIL first. Boiling is not 100 degrees, the boiling point at THIS ALTITUDE is.

When water is heated (outside in the garden for instance), air dissolved in the liquid begins to escape into the atmosphere as steam (you don't necessarily see this usually). The temperature at which it boils depends on the pressure of the atmosphere. This is why pressure cookers cook food faster. They decrease the pressure allowing the boiling point to increase. Once this is achieved, a higher temperature can be achieved.

When water BOILS, air is being dissolved into the atmosphere very quickly, this is seen as bubbles allover the place, and can be heard as splashing water. So water can freeze and "boil" at the same time. (or be 10 degrees e.c.t)

 

[madmike159]

What I find mind-boggling and unable to grasp is the extreme smallness of atoms and the extreme vastness of the universe. I work with these concepts and numbers all the time, but it's hard to get a feel for it.
Take a glass of water. It has about 3\times 10^{25} molecules. I can hardly grasp the vastness of this number. If this glass of water were mixed throughout all the oceans of the world, then a glass of water, drawn anywhere on earth, would contain many molecules that were contained in the first glass.

The all of the freshwater in the world (3% of the total amount of water) has been through an animal... Yuck

Another interesting thing I heard is that if you put a bottle of water in the freezer and take it out before it freezes, if its cold enough when you hit it with something it freezes. Or atleast the outer layer does.

 

[madmike159]

I'm thinking of another weird fact about the subatomic world, but I can't fully explain the details, I would like someone to say more about it:

The protons and neutrons making the nucleus of every atom, due to its confinement in such a small region of space, vibrate moving at incredibly high speeds, a substantial % of the speed of light.
As dictated by relativity theory, at such high velocities the rate of passage of time is much slower than it is for us.

So it's kind of paradoxical that we as a macroscopic chunk of matter age at our usual rate, while the particles we are made of are aging at a much slower rate ...

Could someone confirm, in our average lifespan of 70 years, how many years have passed to the protons and neutrons we are made of?

Because time slows down when you approach the speed of light, photons that were created in or just after the big bang are 0 years old where as the universe is 13.7 billion years old. (Many of the original photons have probably been absorbed and re emitted.)

 

[Bunnyhop]

Yeah, I don't think you could get the spoon out of the black hole to see how much it weighs anyway! LOL

 

[madmike159]

Yeah, I don't think you could get the spoon out of the black hole to see how much it weighs anyway! LOL

Why would you put it in there anyway?
Physicists and their crazy ideas

 

[1drdan]

It seems like water will boil and freeze simultaneously on Mars (it would in space). I don't know the atmospheric pressure on Mars, and that would be the determining factor.
In space as water boil away into the vacuum, it would still have to absorb heat to do so (boiling is an endothermic process). It would take this heat from the still unboiled water until it got cold enough to freeze. Hence, boiling and freezing simultaneously.

I heard once that if you took a bottle of water to Mars and poured it out, it would both freeze and boil and the same time!
(don't know if that's 100% true or not, but I found it pretty fascinating).

 

[matvince90]

http://www.telegraph.co.uk/science/6546462/The-10-weirdest-physics-facts-from-relativity-to-quantum-physics.html

 

[matvince90]

Because time slows down when you approach the speed of light, photons that were created in or just after the big bang are 0 years old where as the universe is 13.7 billion years old. (Many of the original photons have probably been absorbed and re emitted.)

That would mean that the whole length of the universe's current existence would happen in the fraction of a second relative to a photon that was created 13.7 billion Earth years ago? That's crazy! Also, would time go in reverse if you were go go faster than the speed of light? The universe is expanding, so something that exists further from the "center" of the universe would be moving faster than something that is closer to the "center". This would mean that speed is infinite, and not limited to the speed of light. You said that time slows down as it approaches the speed of light, what happens when it goes faster?

 

[cdotter]

It's not really a fact, but the light flash phenomenon is pretty cool.

http://lsda.jsc.nasa.gov/books/apollo/S4CH2.htm

 

[DaveC426913]

That would mean that the whole length of the universe's current existence would happen in the fraction of a second relative to a photon that was created 13.7 billion Earth years ago? That's crazy!

A photon does not have a valid point of view, for the very reason you mention.

However, if you accelerated in a spaceship to within a fraction of the speed of light, you would indeed see the the uiniverse age, wither and die bvefore your eyes.

But don't try it, that also means all the light in the lifetime of the universe will fall upon you as incredibly blue-shifted ultra-hard radiation. You'd better put on your shades!

Also, would time go in reverse if you were go go faster than the speed of light?

You cannot go faster than the speed of light.

The universe is expanding, so something that exists further from the "center" of the universe would be moving faster than something that is closer to the "center".

The universe has no centre. All points expand away from each other.

But yes, far flung parts of the universe are moving away from each other at faster than the speed of light.

And yes, that seems to contradict what I just said above. But it doesn't.

This would mean that speed is infinite, and not limited to the speed of light. You said that time slows down as it approaches the speed of light, what happens when it goes faster?

See above.

 

[BobGom]

Interactions between electrons in a solid are very complicated and anything close to an exact Quantum Mechanical solution is pretty much impossible. Yet you can get pretty good results in many cases by treating the electrons as a nearly free gas which only interacts with a periodic lattice of ions. This is despite electron-electron interactions being relatively strong and there being all sorts of correlation effects between electrons.

 

[pzona]

The universe is expanding, so something that exists further from the "center" of the universe would be moving faster than something that is closer to the "center".

Think of the universe as the *surface* of a balloon. Draw several arbitrary points on the balloon to represent different masses (stars, particles, anything really), and then start to inflate it. This is roughly what is meant by universal expansion. Everything is expanding relative to everything else, not expanding from a central point. Imagine the two dimensional surface as representing the three dimensional universe; does this make sense?

 

[Archosaur]

Einstein's biggest mistake was not a mistake.

Are you referring to the cosmological constant? If so, can you explain or redirect me?

 

[Andy Resnick]

I think the fact that every cell in our body has an electric field of about 1 MV/m across the membrane is pretty interesting.