Mystery Definition and 913 Threads

Homework Statement Helium has the special property that its internal energy is directly proportional to its absolute temperature. Consider a flask of helium with a temperature of 20 C. If it is heated to twice its internal energy, what will its temperature be? 1. 293 C 2. 313 C 3. 40 C 4...

Homework Statement Fission reaction: 10n + 23592U --> 14156 + 9236 Kr + 3(10n) Why in the world is there a neutron on the left side of this rxn? Why not just reduce the number of neutrons on the right side to two?

Homework Statement Measurements show that a honeybee in active flight can acquire an electrostatic charge on the order of 90.9 pC. a)How many electrons much be transferred to produce this charge? Ne =5.67*10^8 b) Supposing two bees, both with this charge, are separated by a distance of 14 cm...

Average density of universe is 9.3 x 10^-27 Kg-mass/M3. Volume of Cubic-Light-Year is 2.7 x 10^25 M3. Result is .25 Kg-mass/CLY. If Dark Matter is 5 x ordinary matter then 1.25Kg-mass of Dark Matter per CLY. What if there was a billion times more Dark Matter in a galaxy than in the space between...

greetings, what is the meaning of a zero watt bulb?how can be any bulb glow without any power consumption? thanks

I am a bit confused by this observation. Every tensor is it's symmetric plus antisymmetric part. Thus for the components of a (0,3) tensor F_{\lambda\mu\nu}=F_{[\lambda\mu\nu]}+F_{\{\lambda\mu\nu\}} and if I write this down explicitly I end up that for the components of ANY (0,3)...

i know i haven't understood the concept of eddy current and that is why i am posting this question: why are EDDY CURRENTS circular?

Hi, has anyone else seen this news item http://www.physorg.com/news/2011-01-math-theories-reveal-nature.html on how to crack partition numbers using fractals? It came out on Thursday the 20th Jan 2011. They gave a tantalising glimpse and said the full new theory will be revealed on Fri 21 st...

Hi there. I'm a second-year physics student. I'm from Mexico (so please, forgive my english), and I'm on winter holidays. I've been studying Mechanics with the first volume of the "Course of Theoretical Physics", by Landau and Lifgarbagez, that awesome though hard book series. My study plan...

hi, i was just wanting to get a few opinions on where and maybe even when a black hole goes to. It's something I've read into a lot in the past few months; and I'm really interested to find out what others think. Thanks

Homework Statement I need help to decide if the series below are convergent or divergent. \sum_{k=2}^{\infy}(\frac{1}{ln(k!)}) Homework Equations The Attempt at a Solution I tried using the d'Alembert ratio test but the ratio is 1 if I calculated it correctly and then nothing can be said...

I came into my engineering class this morning and our teacher showed us this strange material. He got the material from a student who recently went hiking. According to the student, he and his father went into the woods and started a fire in an old metal tire rim. They threw a bunch of old...

Homework Statement Why when a Tippe top is spun with high angular velocity, it spins until it lifts its body of the top off the ground with its stem pointing downward? Homework Equations The Attempt at a Solution The only reason I could think of was that it's kinetic energy is...

I have to finish my investigation and the outline has something called a Theory review. It defines it as: a story that generates interest in the reader for the field of your research and link to practical investigation to follow.:confused: Now this maybe very simple but I'm not sure what kind...

I recently realized that we use this concept constantly but I have absolutely no idea how I would answer this. Never in any school physics lesson or university lecture I've attended has anyone even mentioned this. It's just sort of taken for granted because we all have experience of it passing...

What do they mean with "faint regime", when they talk about cosmological explosions?? (e.g X-ray flashes) thnx

Hello. I'm new to the forum, and a non-expert trying to learn about topics for a mystery I'm writing. Hope someone can tell me if this is plausible: Drilling equipment on the seafloor either malfunctions or is sabotaged in a way that shoots a stream of water mixed with seafloor sand upward...

Homework Statement What physical phenomenon requires us to work with probability amplitudes rather than just with probabilities, as in other fields of endeavour? Homework Equations The Attempt at a Solution Not sure. The wording of the q throws me... phenomenon i.e...

Here comes a pretty hard question, which not even my QM teacher has been able to answer. When we think about one hydrogen atom, and put it in an electric field along the z-axis \bar E = \bar e_z E. Then the potential for a hydrogen atom will look like this: U = -\frac{e^2}{4\pi \epsilon_0...

http://www.theglobeandmail.com/news/world/americas/pentagon-stumped-by-apparent-missile-launch-off-us-coast/article1791785/ https://www.youtube.com/watch?v=CeXNC8k9FKU

Hi Guys, I understand that the energy associated with wind damage from a hurricane goes as the third power of the velocity of the wind. How is this relationship derived? I ask because when I think of wind energy, I think of Kinetic Energy going as the square of the velocity...

In my reading I came across the equation ds2 = −dt2 + 2t/r dtdr + (1 − (t/r)2)dr2 + (BKr)2(dθ2 + sin2 θdϕ2) where s is spacetime, t is time, r is radius and the others are not important for my question. What I do not get is the "1" in the (1 − (t/r)2)dr2, or dr2− ((t/r)2)dr2 . This seems...

Homework Statement What causes the faint rainbow outside of the primary one, and why are its colors reversed? Homework Equations I know that rainbows form from passing through raindrops but I don't know about the second one. The Attempt at a Solution

Homework Statement Two beads of mass m are initially at rest at the top of a frictionless hoop of mass M and radius R, which stands vertically on the ground. The beads are given tiny kicks, and they slide down the hoop, one to the rigth and one to the left. What is the largest value of m/M...

http://www.youtube.com/watch?v=Y6a4T2tJaSU&feature=player_embedded Just for fun, more than anything. But you got to admit, it is intriguing, particularly if you watch the scene more than a couple of times. It does seem that she (he ?) is talking into a cell phone .. in 1928. And no, I am...

I have uploaded the pic of schematic of two type speaker. The left side of pic shows the usual one speaker where sighnals are fed at both the wire of the coil. 1) I assume the right side of the pic(speaker)(which I imagine) should work , where I have grounded one of the coil and ths signal is...

Homework Statement Work done by conservative forces = -\DeltaU Homework Equations Above. The Attempt at a Solution Here is the whole equation: Wc+ Wnc = \DeltaK. Wnc = \DeltaK + \DeltaU. So, Wc = -\DeltaU. But, for example, how does that apply in a situation with no...

wormholes...a mystery or not! do wormholes actually exists? if yes, then, is it true that they act as shortcuts for some other destinations in the universe? and lastly can man himself create them!?.....all a mystery 4 me!

Why doesn't the Higgs field give photons mass?

http://wjz.com/local/honey.bees.2.1953775.html

What, in your opinion, exactly is smart? Is it looking at someone and seeing something no one else does? Is it finding a new way to do something? Or is it by being the cleverest?

Homework Statement The base-emitter voltage, V_be, typically never exceeds .6V. Because of this low value, the base-emitter junction must be protected against too high a reverse voltage. A diode is usually used to protect the junction as shown in the figure for a npn transistor. a. Explain...

http://www.higgs-boson.org/ Is it as garbage as it looks?

How does dark flow work? Thanks

Homework Statement 25 cm3 of 1 mol/dm3 ethanoic acid requires a smaller amount of sodium hydroxide for complete neutralisation than 25 cm3 of 1 mol/dm3 hydrochloric acid. True or False? 2. The attempt at a solution I selected true, but I was wrong. Both of them require the same amount...

http://www.electronicfog.com/ Duno - it doesn't seem very believable to me but a friend of mine seems to be very convinced about it and is cussing me out about it ><" Is it basically just another one of those Bermuda Triangle superstitions/stories/myths? Thanks in advance

Homework Statement Once upon a time the famous archimedes was given a problem to determine if a crown supposedly made of pure gold actually contained some silver. If Archimedes was your lab partner, explain how the two of you could quickly determine if the crown were gold or not without...

Is there any mathematical formula to predict / generate / or test the prime number??

how many types of brain signals are there? or if a person thinks of writing a word the signals that perform this action what are those called..? (brain signals is not my subject but i want this knowledge to further use it in a signals and systems project relating to human brain) thnx

If galaxies aer expanding fast than the speed of light how are we able to see them. At the moment this expansion surpassed the speed of light shouldn't these galaxies dissappear or remain unchanged visually?

Please, This equation is based on the free energy of perfect gaz : F = F0 + kBT log c + ½ cb1 + O (c2) ½ cb1 is the excluded volume term (c is the concentration) but what is O ?

Homework Statement Atmospheric pressure is 100 kPa and a depth of 1m in water is equivalent in pressure to 10 kPa. A jam tin, open end down, is forced under water until the water half fills the can. At this stage, how far beneath the surface is the can? (ans is 10 m) Homework...

while reading curved mirrors we come across a term denoted as Q(the distance of image from the mirror)but as the image is formed right on the mirror so the distance of the image from the mirror should be zero?? which is of course not the case.

A particle traveling at 0.5c for 1 second covers 1.3E8m (speed=.5*3E8 and gamma=.866) and not 1.5E8. The average speed was then 1.3E8 m/s = .43c and not .5c. What is going on here? Was it travelilng at 0.5c or at .43c?

Homework Statement A car moving at constant speed of 40 km/h in a straight road which heads towards a wall makes a 900 (90 degree) turn by the side of the wall. A fly flying at constant speed 100km/h starts from wall till car and when it reaches the car turns back and flies towards wall at...

im having a hard time understanding just what it actually is. I've heard about WIMPs and now quirks. But i know we can't see it, but how dose it affect us? Why does it emit no light? I've also heard about the big crunch saying that if there is too much matter in the universe it would...

I was trying a simple Darlington circuit with two Darlington-connected NPN transistors. There is an LED in the shorted collectors, connected to a 5V supply, and the base is open. The trivial objective was to see that when you touch two fingers to the base and the supply positive, the LED turns...

If you could build a box with a reflective inside that no light could escape. If somehow you put a laser in the box and fired the beam and then shut off the laser what would happen? Would the beam continued to bounce off of the insides of the box or would the beam dissipate somehow? If it does...

Saw a reaalllyy bright star-looking object in the sky tonight after looking online, I'm thinking it was Venus. That what all the articles online are leading me to believe. so... Has anyone else seen it? it looks amazing to be honest. I really wish I had a telescope.

I just saw a commercial for http://rgbytv.com/" I understand how additive color mixing works, and how the addition of a yellow channel would allow for the creation of more http://www.ncsu.edu/scivis/lessons/colormodels/color_models2.html#saturation." yellows, but if we only have RGB cone...