Physics

Is there theoretically any way to detect heat beyond a barrier, without access beyond this barrier?

Is there a way to make something undetectable to echolocation?

can someone please explain to me the theory that black holes can distort time? because to me i doesnt make any sense Merged post follows: Consecutive posts mergedi just realised this is probably in the wrong section but oh well

Did Isaac Newton really discover the law of gravitation when an apple fell from a tree and hit him on the head?

Michio Kaku said this when describing the work of gravity in one of his many shows on the science channel. I was wondering what is meant by this and why it's important to view it this way?

Original Article : url deleted Holography is a type of data recording technique used, primarily for image recording. Holography is so famous because it can record the image in 3 dimensional wise. Also it's also proven to have higher capacity than conventional storage method. You'll most likely to find it in your ID card, where a logo is imprinted on your card. Holography was discovered in 1947 by Hungarian physicist Dennis Gabor (1900–1979) work for which he received the Nobel Prize in Physics in 1971. The theory behind holography is the interference of light. A monochromatic light is split into 2 equal and coherent beam by mean of a beam splitter, …

can the electricity stored in a capacitor be released slowly and controlled?

what is difference between earth and world (in terms of physics)

White light is a mixture of all the different frequencys of light but it can be seperated by a prism. What I want to know is: How does a prism seperate white light into its components?

Since we can only see visible light, how was the electromagnetic spectrum discovered? How were X-rays, gamma rays, microwaves and radio waves discovered?

I'm attempting to understand their difference, and their relationship. The Electomagnetic Specturm ranges from Gamma Waves to Long Wave Radio waves, and everything in between. Electromagnets and other kinds of electronic equipment and power lines give off electromagentic fields. My question is, are the electromagnetic fields emanating from electronic equipment and other electromagnetic sources, part of the Electromagnetic Specturm? If so, what portion are they in? If not, what is their relationship?

I recently watched a documentary on Boltzmann, which was very interesting but continually likened entropy to disorder (and "decay"). Wouldn't it be more appropriate to liken entropy to the information content of the universe, and to state that the information content of the universe is increasing? In other words, the universe is complexifying. I've heard it argued that some types of complexity, such as the arrangement of molecules in a gas cloud, are not particularly important/useful/meaningful. Also I suppose as the universe reaches a state of extreme old age and approaches absolute zero it is no longer meaningful to liken entropy to complexity. Thoughts?

When an empty bottle is placed in the water, it will never be able to float upright. Why is this so?

What is the differences between motion and movement?

I have come to the conclusion humans were created to co-exist with the Universe, in which case the Universe was made for us, for without us it serves no purpose. Before the humans & animals came to be, you had the Universe. Space, stars, planets etc. We can be certain that the microscopic particles and atoms do not have the intelligence to comprehend their existence, correct? The humans, & a majority of animal species have what is called an eye. Light is reflected off matter, passed through the eye and converted by our brains into what we see (the visiual). We can see planets & stars, they can’t see themselves. Meaning their magnificence & beau…

Ok, as I was advised to tell you all so as to avoid undesirable responses, I have looked around on wikipedia and google for an answer, but I can't understand any of it. I'm an english major that likes science, and as such I cannot comprehend anything about the M-Theory or String theory or the other stuff that pops up in searches. Is there definitley more dimensions than the three that we know of? Is time considered the fourth dimension? And if so, does that mean that entities that reside in this dimension could manipulate time as we manipulate the spatial dimensions (hypothetically speaking)? Could we live or even travel to higher dimensions? Or could higher-dimen…

A stone falls into the water and water drops are splashed. Why do the water drops fly upwards? Does the maximal height reached by the drops depend (primarily) on the size of the stone or on its speed? What is the maximal height?

So, I was thinking about gravity. Now, I know how gravity works. But my question is this. The further away you get from an object, the less the gravity is apon it. Also, I know about the orbit or w.e thing. So if you are 100 miles off the earth, going at the exact velocity to keep you in geostationary orbit; if you raise the height of your orbit 1 more meter, your speed is no longer fast enough to keep you in geostationary orbit, since you would need a faster speed due to the increased circumference. What isn't added into this thought is the of the decrease in gravity's effect apon the satelite. This means that not only would you be going 1/10th slower than …

Can anyone confirm to me that it would be FAR easier to send a rocket into orbit right at the equator? Also, it would be far less easier to get something in orbit spinning the same direction as the Earth as apposed to the opposite direction. I can't see why this wouldn't make sense, but I want to make sure i'm correct before I add it to my book of things I know

I am trying to populate the nozzles in an ink cartridge with ink. The 45 micron holes have tape over the outside of the nozzles and I need to populate all 512 nozzles with ink from the inside. I was thinking of creating a vacuum inside the cartridge i.e. taking all of the air out of the cartridge and then releasing ink in. and hoping that these micro holes then replaced the vacuum with ink but I am not sure if this will work due to the surface tension of the ink. Does anyone have any ideas how I could do this please?

I've been just thinking, as I do, and thought.... What volume of iridium would produce the same gravity as earth? How much smaller would a sphere of this be than the earth? Hope someone can help here.

Recent experiments http://www.nature.com/nphys/journal/v2/n6/abs/nphys316.html confirmed theoretical results that electrons are not undividable as it was believed -for some conditions it's more energetically preferable for them to separate their charge part (called holon or chargon) and its spin part (spinon). I think it's a good time to discuss about these results and their consequences. Thinking about 'pure spin' (spinon) made me associate it with low energy electron neutrino, especially that I imagine particle's properties which can only occur in some integer multiplicities like charge or spin as topological singularities - such separation greatly connects t…

Okay (he says with a redundant sigh). I know how it is that water, prisms and the like have varying indexes of refraction for the coloured constituents of light, thus breaking up "white" light, into all the visible wavelengths. (the pretty colours of the rainbow) However, my question is, why does a rainbow typically appear as an orderly arc in the sky? What is going on? Is this question one of human perception, or the science underlying the phenomena itself? I'm confused. (Theo forges a smile, in order to adequately express his thoughts) > ! (adding an exclamation point for effect )

I'm new to SFN, greetings to all. I've been working on hydrogen generators using 316L stainless anodes and cathodes. The anodes oxidize away. Potassium hydroxide is added to distilled water. Will a coating of DuPont™ NAFION stop this? I have a vaccume pump hooked to a tank with electrodes and it seems more gas is produced with a vaccume of 25 reading on the guage. I thought that water would cold boil at a vaccume. At what reading? When it turns the water to gases is there away to pull out the oxygen leaving the hydrogen? Did I post these questions in the correct forum? Thanks, Brian (info@hydroasfuel.com)