Physics

There was a point when almost nothing was known. I am wondering, how do you think people like Einstein started on the road they did to even begin to discover the things they did? Imagine that nothing were known about physics and the world we live in except what you can literally see. How do you take that first plunge into atoms and gravity etc.?

We know very well gas molecules moving fast at high temperature. Then, what makes gas molecules moving fast at high temperature? Low temperature -------> high temperature How to change radiation energy to kinetic energy?

John von Neumann gave a formal axiomatic treatment that united the equations of Heisenberg and Shrodinger in 1932. This is one of his astonishing achievements in physics and many other fields. I'm writing a book on Johnny (his preferred name) and would like some opinions on the gravity and staying power of his work. Thanks.

is it safe to store my medication in a wine cooler at 66F? My room temperature is 80F. I am worried about condensation forming on my meds. My medication (benzos) is vacuum sealed in a glass jar so there shouldn't be any moisture problems. However, I've heard that storing medication in refrigerators is a bad idea because taking your 40F medication out into room temperature of 80F will allow condensation to form on your pills. But since a wine cooler is warmer (66F/19C) than a refrigerator, would it still condense or is it safe? Would simply allowing the vacuum sealed medication to return to room temperature before opening the vacuum seal and taking out the meds…

This is probably a question better suited to a history forum, but since it does largely involve basic physics, I thought I might as well just post it here. I recently watched a documentary on the famous Battle of Thermopylae, and I find myself at a loss to explain how the Spartans managed to hold their ground against a charge of thousands of Persians. In the pass there were 300 Spartans forming the phalanx blocking the Persian army from accessing the pass, and they were up against literally thousands of Persian soldiers. What I don't understand is this; as strong and well trained as the Spartans were, the fact remains that they were still only 300, backed by about 8000 ot…

Ok, so this needs a bit of explaining. I'm a very amateur scientist... well actually I'm really a sound designer, that is amongst other things I create sound effects. I'm also naturally quite curious and like to ask the question why? as I'm sure do you. So my interest in this topic stems from some sound effects, namely the very famous star wars laser sound created by Ben Burtt which was a recording of himself hammering a steel guy wire. As I understand it the phenomenon of acoustic dispersion is responsible for the high frequencies in the sound moving faster than the low frequencies. Other examples of this sound are this great recording under ice sheets: http://s…

Hi, I have a basic question. I was wondering if anyone could please let me know its answer. we know that the atoms interact with each other according to a force-field based on namely LJ potential but there is not any viscous force that reduce the relative velocity of pairs. So, if we apply an external force along the nano channel, we expect that the atoms accelerate and their velocities increase infinitely. I wanna know what is the origin of formation of a Poiseuille velocity profile and not a plug flow? Thank you AMd

If you build a transmitter with a frequency of about 700 THz will its antenna start emitting visible violet light?

There seems to be some controversy around this topic. I initially thought that it's the gyroscopic effects keeping it upright ( which was supported by the fact that a bicycle may roll downhill by its own), but then I met the argument that those effects are not very strong. I agree with this argument because I think the gyroscopic effects felt by the bicycle is sufficient enough to support a riderless bicycle, but not one with a rider. I mean, a bicycle just weighs a few kilograms, but I weigh 60kg! So the effect it not powerful enough to support me. Am I correct? I came across another theory that; "our brains learn to keep the bicycles upright by making necessary…

I was about to start a thread in the Speculations forum, but then I got to thinking, is it even going to be possible to discern whether Gravity is faster than Light?

In a physics discussion when during lab times, we had to measure the speed of sound forming a standing waves in a long tube filled with water, by adjusting the height of the water in the tube. Now the frequency we produced was directly from a tuning fork, not some machine, so after we tap on to the tuning fork, we put it above the tube and listen to the loudest sound it produces. My question is how on earth do you get the uncertainty values for the tuning fork or the frequency? i mean i know the other uncertainty values such as the wavelength etc... you can calculate them through the uncertainty of the height of the water column on the tube. But i have no idea how to…

dictionary shows Axiom can not be disproved. do we need any arbitary derived constant or experimentally measured value or emperical derivation to form theory if theory is based on axiom. Is there any theory out there based on axiom?

Hi. Which metal made thick walled container, [not foil] about the size of a coffee cup with a lid can be put in a microwave oven so the metal will heat up, heating its content by convection inside ? Would an iron, stainless, aluminium, brass, copper... cup work without damaging the oven nor making fireworks ? Or some other material that will absorb oven microwaves ? Would its shape spherical, no sharp edges... be preferred ?

Hi all, does anyone have any knowledge on ferrofluids here? Is it more of a chemistry question? Anyway saw this article in the new scientist magazine regards ferrofluid for central heating. It seemed like a reasonable idea and wondered if anyone on here could see why it may not be viable. http://books.google....heating&f=false Secondly, does anyone have a fairly basic formula/calculator for predicting energy consumption of solenoids. Many thanks

Hi Got stuck in a calculation. Any suggestions will be highly appreciated I am trying to calculate the RI and other optical constants for an acrylic slab (thickness = 1.65 mm) - TAKING MULTIPLE REFLECTIONS within the slab into consideration. I took the reference wave and the sample wave. Calculated the phase change to be 34 degrees. I deduced some equations of T, phi ®, phi (t) and beta and alpha. But there are too many unknown parameters to solve the equation to get the value. WHAT SHOULD I CONSIDER TO CALCULATE THE REFRACTIVE INDEX CONSIDERING MULTIPLE REFLECTIONS WITHIN THE SAMPLE.

if energy cant be created or destroyed, then what was the energy that was transformed in to Dark energy? and what could Dark energy transform in to?

Decay scheme help I would like some help interpreting some information about a radioisotope antimony 126. The data is on page 4,5 and 6, I think I understand it but would like a second opinion. Is the max energy Q=3665, if so what is the average? What are the main decay energy’s for Sn126->Te126 for the 19.5min isomer and the 12.5 day decay path and what for are they in (gamma/beta) Thank You +energy sn126.pdf

Purely out of interest, does anyone here know what this equation- extracted from an episode of The Big Bang Theory- is about? (other than nuclear physics). It gets sheldon cooper (despite being fictional) stuck, and he's meant to be genius. From that, and that alone, I'm assuming it's something pretty complex?

Hey people of SFN, I LOVE all sciences!! But mostly Physics and I was woundering.... Is there any qualifactions to actually call yourself a physicist (e.g getting a Masters degree)?

Does it matter if a bosun meets an anti-bosun?

In a universe which does not contain any mass what-so-ever i.e. every single particle is a massless one, would spacetime actually exist? Or would existence be simply a zero-dimensional point?

rainbow normally occurs when rain drop suspended in clouds are passed by light ray of the sun which reflect 7 colors. the question here is that what phenomenon causes rainbow?

What would be de radius of the event horizon of a blackhole having the mass of the universe ? Same question whith the barionic mass of the universe ? Just a curiosity...

Can anyone explain to me why exactly it is that radioactive material decays at an exponential rate? To make my confusion more clear, take the following example. Let's say you have 1 gram of radioactive material, and for the pure sake of argument, though I admit that I'm just pulling this number out of a hat, let's assume that 10 trillion radioactive atoms are in this gram. The half-life of this fictional radioactive material is 1 million years. Now before I go any further, I just want to make it clear that I more or less understand the mathematics behind radioactive decay (N=N0 x e^-kt), so I don't need an explanation of that, or of how to use said formula. Now, e…

Hi guys! We're 5th yr architecture students and we would like your help please!!!! we are currently doing a thesis about an interactive museum of science and technology and we would just like to ask if you have any information or suggestions concerning on the topics of Physics and its experiments. THANKS!!!!