Mystery Definition and 872 Threads

This has been bugging me for years, but I never thought to ask about it before. I always thought that the 'ring' trigger signal was just sent to the phone from outside and set it going. What I've noticed, though, is that two phones on the same line don't ring at the same time. It's very...

Hello, the question is above...now all I know is that all the colors combine to make white. Can you help? Thanks

what exactly is number theory i have heard of it but i don't know what it is

A question has been puzzling me: why does a steel specimen feel warmer after it is fractured via applied tensile stress?

Homework Statement http://img220.imageshack.us/img220/2813/graphmo4.jpg [/URL] Homework Equations Not necessary The Attempt at a Solution The answers that I have up there are correct, but I was wondering why graph 2 did not look something like this...

Simple question here, I know where the protons, neutrons etc. are, but what I can't seem to find anywhere is what I have labeled "X" in my poorly drawn diagram. Everywhere I look it calls it an "electron cloud" is that all it can be described as because we don't actually know exactly what is in...

[SOLVED] Quantum Numbers What is the difference between using J and l for quantum numbers? I have some lecture notes that aren't fully explained. It was talking about rotational transitions for diatomic molecules, and said the energy of a photon going from level J to level J-1 is...

How can there be three forms of the double-angle formula for cos 20?

In the cellar you have three light switches, one of which turns the light on in the attic. You can only go upstairs once to check the light in the attic. Which switch turns on the light?

Hi, I'm not good enough to contribute answers yet, but I hope to entertain you with questions. Practically all the Earth formation stuff I've read talks about the Earth being molton. That always seems strange to me. If I think of a space body without an atmosphere, I generally think of it...

Where did everything that went 'bang' come from ? It would seem to me that even potential must have a source of origin. Accepting that the Big Bang is true, where did it come from ? Where did all the potential of the unified field come from that went 'bang'? What caused all the 'matter' of the...

How are you at guessing or even knowing what some of these are? http://puzzlephotos.blogspot.com/2006/01/mystery-objects.html

negative force! can anyone in this world,tell me what is negative energy... how does that help in transportation... heard that if it really existed,we can travel large distances in few seconds please do help folks

I had a test today that was really tough. We just went over conservation of momentum and angular momentum and that stuff. The hardest problem on the test looks like this: http://alexmabee.googlepages.com/problem.jpg/problem-full.jpg I can't for the life of me figure out how to solve...

Homework Statement In a ride called Drop Out, riders are spun in horizontal circles of radius 5.5m, which forces them to the outer wall. When they are spinning fast enough, the floor drops out, and they are suspended by friction. The coefficient of static friction is 0.28, how many rev/s must...

Homework Statement Say I have a potential that is infinite from - infinity to 0, -V_0 from 0 to a, and 0 from a to infinity. Then I have three unknowns, two for the plane wave solution in the finite well and one for the exponential outside the well. But I also have four equations. Two...

Homework Statement Hey just a quick question that bothering me: how come when u stick your finger in the middle of the fan and let it move it goes in a larger circle?

I've been puzzling how it is that you can tune into a signal on a particular frequency. How can it be possible to get rid of all the other signals that are added together? I don't know how much of this makes any sense, but I have tried to specify the problem mathematically. Suppose R_1(t)...

Today's "What is it?". Can anyone quess? If you ask, I will give hints. http://img156.imageshack.us/img156/6198/whatisitlc9.jpg

Heat is the the vibration of molecules in a medium. If this is so, then how is space cold if it is a vacuum. I'm aware that space has very few particles but I don't understand how heat is emitted. I'm guessing that it might have to do with radiation.

Say you take pi and keep zooming on on a circle. You keep getting more digits but you never actually hit the end of pi. It has been proven to be infinite. But how exactly is something infinite constructed in our universe. It just doesn't make sense to me. Almost as far as saying that the...

Are there natural gas powered heat pumps? My friend says yes, but the science is puzzling to me if so. Easy to understand burning gas to make heat, but what economical home system can make cold air from hot burning gas unless the heat turns a dynamo that makes electricity that powers the AC...

Apparently what I thought I understood about waves is wrong: there seems to be a net momentum transfer with mechanical waves, as well as photons (it seems they're perfectly analogous). I hope some of the experts on the board can help to clarify this issue; perhaps it’s less surprising to...

I found a folder of ancient motorbike mags on my porch, can you imagine my joy? No one loves or even likes me enough to give me such a gift, they are probably priceless, well worth a few bob anyway, who the heck?

k the question states On a pleasant fall day (temperature of 21.0 degree celsius) a lump of clay (with mass of .855 kg) is thrown against the wall with a speed of 38.0 m/s. The clay deforms as it sticks to the wall, noiselessly. Assuming no heat escapes into the air, what will be the...

Riddle 1 30 Prisoners are on death-row for marijuana related offences. The prison warder doesn't view their crimes with much seriousness,and decides to give them a chance to escape.He makes the prisoners the following offer: Tomorrow all the prisoners will be blindfolded, and either a black...

I wondered why it is that when you multiply a negative with a negative, you get a positive? in example; why is it that -3 x -3 = 9? when you do -3 x 3, the answer is intuitively -9, because you just go three times as negative. But when I multiply two minus signs, I don't have this...

For the past year I haven't been able to keep milk in my fridge for more than 4-5 days. I always buy the freshest milk, not expiring for a couple weeks from purchase. However, the milk sours in my fridge in 4-5 days no matter what brand or size of milk. After 4-5 days the top of the milk is...

Carbon dating! A 5g charcoal sample from an ancient fire pit has a 14C activity of 63 disintegrations per minute. A living tree has a 14C activity of 15 disintegrations per minute per 1g. The half-life of 14C is 5730 years. How old is the charcoal sample from the ancient fire pit...

One of the factors that can produce a winning F1 car is the understanding of turbulent flow, the people that design these cars spend millions on wind tunnels, simply because turbulent flow has not yielded to mathematics, my way of thinking is ,that it is essential to understand turbulent flow...

This is a very curious situation. I have a large water tank on the top of a hill. It supplies a gravity fed water system that works fine. There is an under ground pipe with one end A in the bottom of the tank. The other end E is about 80 feet below A, and has a faucet. None of the pipe is...

what does a big inverted V stand for? it's not "and" because it's used right in front of a literal (atomic formula) not sure if it's a quantifier... This is a paper discussing approach based on deontic logic that I am scanning through, but this sign i cannot figure out how to search online...

I'm just wondering whether anyone has any theories as to what causes the electrons in the Aurora Borealis to accelerate (emitting e.m radiation)?

It is often stated that ANY accelerating charge radiates, so this includes uniformly accelerating charges. But the radiation reaction force is proportional to the THIRD derivative of x, so it vanishes when acceleration is constant. What's the deal here? Here's a graph which supposedly shows...

I'm often slow on the uptake, but this is ridiculous. I just figured out what the pointy hair represents in Dilbert's pointy haired boss.

How does cold air travel? Isn't it like me flashing darkness at your face? Because cold is the absence of heat as darkness is absence of light. It's like nothing traveling. I know it's confusing.:confused:

Hi everyone, I have just read an article about the discovery of a ring of a dark matter. In fact I do not understand this matter very much, except that it has great gravitational field in space. Can anyone explain shortly about that or just give me some web links that I can read about that...

I'm currently going through some questions and came across quadratic and linear simultaneous equations. Solve the equation: x + y = 1 x^2 + y^2 = 16 I am not interested in the question itself but rather the explanation the book gives me which says after...

I just read that the mystery of the "missing solar Neutrinos" has been solved. That is, the "missing" stuff is converted to Muon & Tau Neutrinos (which have been detected at the SNO). I'm confused ... If Solar Neutrinos are very "non-interactive", then how do enough of them get converted...

I was wondering, if dark matter (DM) halos are spherical in nature and increase in density as a function of distance from the galactic core, why does the density drop off so suddenly and why would stars on the edge of a galaxy feel an inward pull? To elaborate on the 2nd question, if DM...

I thought optical phonons only existed in crystals with two or more types of atoms in a unit cell. But I keep reading references of optical phonons in single atom crystals, like silicon. What's the deal here?

So black holes are incredibly dense points of matter that affect everything in their area with very powerful gravity field, including light. \ So, asuming that gravity affects only matter, that by default says that light is a physical particle. So why don't the regular laws apply to it...

Hi, I've been learning about transistors lately through the Horowitz & Hill book. I'm surprised to see that when used as a current source the collector voltage only changes with load voltage with an ideal transistor. When I say I'm surprised I mean that in non-ideal models the base current...

Simultaneity Let's imagine there is a train moving at the speed of light. When in the middle, two lightning flashes appear on it's left and right. Why is it that it sees the right flash before the left? And if it is moving left to right, why does it see the left before the right? It is to...

I found a powder in my driveway earlier today. I have no idea where it could have come from but I'm curious because it seems so out of place. It's very dark brown, almost, but not quite black (see attached) and utterly uniform in colour. It's extremely fine, finer than icing sugar. So fine...

Hey Chem geniuses! I am a struggling high school chem student who couldn't combine water with water without blowing something up so some help would definitley be appreciated. My chem final has been issued already and it is as follows: Put 5 mL of 3 M aluminum chloride solution in each...

http://www.collegehumor.com/video:1755006 This may be old but... How does this work? They need to have a huge warmth transfer coefficient for this to happen? Maybe the water is at 0°C already and a small amount of energy should be taken to get this effect. Is it electromagnetical or is the...

I just read the following fact and it somewhat defies my usual logic. \lim_{x\to\infty} \sqrt{x^2+x} - x =\frac{1}{2}. Now my usual logic tells me that as x becomes large, the leading term in a polynomial sequence is the major one and therefore the x^2+x becomes x^2 so \sqrt{x^2+x} becomes...

So I learned today that Bleen is the integer number between 6 and 7. You might be a little upset about this. However, bleen can still be useful to you, since it is also related to Grue[/color], a very convenient term not to distinguishing blue from green in language[/color]. The philosophical...

Say we have two waves of the same amplitude are about to collide with each other. The preceeding wave travels at a slightly higher speed before interacting with the final wave. However, instead of passing through the final wave its speed and size is transferred into the final wave where it...