Physics

time is indeed directional. it is the increase in entropy. and that increases. yes you can go BACK historically to refer to a state of the universe where entropy was lower and disorder of energy lesser. but that was back where things were. and now, from moving, no matter which way they move the disorder is greater and thus it is a further point in time. to reach a previous state of entropy of the universe you need for everything to unmove, an impossibility as far as we know. it was a previous point of motion. motion causes all things to become into more disorder. thus time is directional in the forward way. because by virtue of motion the universe must increase in disorde…

If light can't escape a black hole that means its pulling faster than light. If you went into a black hole flat against an object and at the moment you hit the event horizon you somehow went fast enough to push yourself off that object wouldn't you be going faster than light since your speeding up your descent into the blackhole which is faster than light? I'm probably wrong I'm just a kid with a wierd thought.

Is it true that no physical coupled gear with a two meter radius could spin (accelerate) as efficiently as these MagGears? http://elanetics.com/physicalgears.html Want to make sure this statement is correct.

Refraction. Why do light always bends towards the normal when entering from one medium to the other? Why not away from the normal?

I was always really confused about the concept of the 10 (and now some believe 11) dimensions. I came across this video that explains it in a simplified form (it's a video for the first chapter of a book): http://youtube.com/watch?v=qU1fixMAObI Pretty interesting. I got lost a few times, but I get it now!

As we all know that the earth has more attraction power than the moon.Then why don't the earth attracts the moon and moon collides with the earth?

Now first off I would like to say that I don’t know for sure that time travel is possible or impossible, I would just like to lay my thoughts out on why I Think its impossible. 1)I don’t know of anything in nature that we observe to travel time in the sense of simply disappearing to another time. I don’t know of any experiment or set up for such that can produce such results either. 2)If for instance if time travel is possible. To travel to the future or the past implies a few things. First, for the smallest amount of time, for whatever that is, each passing moment of such then is perfectly recorded, or time is perfectly contained or else you have information bei…

Hi, Just wondering if there is anything that you can paint or stick onto the 'attracting' part of a magnet to stop it being so magnetic? thanks

Say you have two black holes of equal mass, equal distance apart from each other, in fact the black holes are mirror images of one another really, what would occur if they were close enough to act on each other? Allow for no other variables to exist in this environment, such as another planet for instance, its just the two black holes. *Its a thought experiment I guess, I don’t know where I should have placed it. So if an admin wants to move such, go ahead I am fine with that.

especially those sports ball. please help me with this. I'm not familiar with the terms they mention in the internet. thanks!

Ok, say it is the middle of the day and you are accellerating beside another car down the road... why is it that you see there wheels start spinning backwards as they accellerate? Is the sun flickering or do you see in frames... or is it something else? I have always wandered this since I was a little kid... Thank you in advance!

Wasn't sure where to put this one... Was wondering what determines the distance of our atmosphere relative to the earth. I mean, why isn't the atmosphere a little tighter, clouds hovering mere hundreds of feet overhead rather than thousands?

I just found out about this; http://peswiki.com/index.php/Directory:Gun_Engine Does anyone know how this think actually works? Anyone have any more info? I can't figure out how it uses the detonation to produce work. Otto engines use the pistons, but what does this thing use?

May not the best place to post the subject, sorry, but : I have never lived in a house with a fireplace. Am a total ignorant on all about them. Planning to install a cast iron freestanding one on a vacation home that has a brick chimney with a ~8" duct inlet, and i wonder where does the air needed for combustion comes from ? If from the living space ; windows and doors must not be 'airtight', must allow some air to leak in to supply the burning ? If very cold outside, any supply air entering would work against the desired heating. If airtight, would the fumes flow freely to the chimney ? How does it work? Thanks, Miguel

what theorys and laws should i read up on or that have a lot to do with astronomy, phyics, jus science in general for example/ the theory of relativity, laws of thermodynamics what other ones should i read up on help appreciated

the speed of sound at sea level and whatever temp is known and has a number or a constant. sound uses air as the medium in my example, I want to know Why you can hear a sound some distance away when the wind is blowing the air across the path of that sound? how come I can still hear across several rooms when there is a Fan blowing across the path, it even works if you use a cardboard tube to listen through. since air is the carrier, surely the sound should stop if that air that`s carrying that sound is moved away by an airflow, and yet it isn`t!? what`s going on?

I'm making sure I understand this. Galileo dropped a piece of lead shot and a lead cannonball off the top of the tower. Because there where the same density they hit the ground at the same time irrespective of them being different weights and sizes (they where both made of lead therefore both the same density). However if it had been a plastic ball and a lead ball of the same size they would have been different densities as well as different weights and the lead one would have hit the ground first?

Can this be bought? I rather like both of those effects, looks fun for practical jokes. Could drop a load of it onto people who are below you. http://gprime.net/video.php/jaylenoinhalesantihelium

I read some explanations and definitions, still do not have it clear. Any simpler wording from any of you, please? (Nuclear magnetic resonance spectroscopy) http://www.cis.rit.edu/htbooks/nmr/inside.htm http://www.scirus.com/srsapp/search?q=%22Chemical+shift%22&ds=jnl&ds=nom&ds=web&g=s&t=all From what I grabbed; when exposing an element to a magnetic field, its resonant frequency changes (shifts) certain frequency. As for Au, it is 1.712690 MHz. For Ag is 4.653623 MHz, ... Now, -That amount of shift corresponds to a fixed reference amount of field, say 7 Tesla. ? -Is the shift less for a lower intensity magnetic field ? -What …

A question from gravity.If I take two things say gold and aluminium of same shape and size and fall it from a buliding , which will fall first or they will fall at the same type?And if I repeat the same activity in vaccum , what will happen?What matters in free fall?

Hi all, im new here so first "hello all" I have a few questions to the smarter members here about Bitter magnetics, i am working on a project based on solenodes, well air core one really, anyway i have gone through the normal copper coils of different sizes number of turns ect and have goten so really effetive results. now i need to make a much more powerfull magnet and i was wondering if a Bitter magnet (air core) would be the way forward. like i said i have made and used coil magnets with upto 10Kv running through them, i can up the power if need be, but it must be a small unit with dimentions like these: id: 7mm, od: uptp 50mm L: upto 60mm I know its …

Hello all, If anyone knows. I'd like some idea of how scientists know for a fact that cosmic rays are a completely separate source of rays from the rest of the earth's sun's rays? On the surface it seems to me almost impossible to separately measure and identify the suns rays, from rays coming from elsewhere in the cosmos. I think this because the sun's rays are sent out in all directions, and would obviously mingle with any supposedly external cosmic rays. I'd appreciate any laymans explanations that make sense. cheers.

Now giving how mass spectrometry works I would like to purpose a question that popped in my head yesterday. Say you have a certain chunk of DNA, would it be possible to use say some type of chemical to elongate it in a tube, and then basically run the length of it with say a type of laser to figure out what each base is? Basically you would put an amount of DNA in a tube or vial type device for example, and then say some type of farmed or culture enzyme would basically uncoil it and make it straight, maybe some type of chemical strip in the vial possibly, and then after the strand is fully elongated you could run a type of laser along it to figure out what each base …

this question was getting to me last night and its annoying the hell out of me. i get that space is expanding and all that but my question is, why doesn't matter expand with it? like if you had a length of spacetime(okay, so, not physically possible) and a length of matter. initially they start at the same length. eventually the space time bit gets bigger but the matter doesn't. why doesn't it? it would seem to me that if space-time was expanding then everything(right down to sub-atomic particles) would expand also.

I'm not a YEC, but I can't figure this out: Q1. Wouldn't an age of billions of years cause the earth's magma to run out of radioactive isotopes? C1. One would think so. (Otherwise, a mechanism to replenish the radioactive isotopes would have to be found.) However, newly-formed rocks continue to contain radioactive isotopes. Q2. What would happen if pure radioisotope samples were generated? C2. There would be a gradually-increasing rate of decay. This would self-limit as the decay rate would make the sample less pure. The rate of accumulation of the isotope and the rate of its decay are factors that offset one another. If the rate of accumulation is nearly …