Mystery Definition and 913 Threads

DISCRETE STEPS IN DISPERSION MEASURES OF FAST RADIO BURSTS (emphasis mine) And no, this wasn't published in April 1st! Link to New Scientist article: Is this ET? Mystery of strange radio bursts from space. Garth

I just show how .999... = 1 Let x = .999... 10x = 9.999... 10x - x = 9.999... - .999... 9x = 9 x=1 So according to the above .3333... shows as 3. Let x = .3333... 10x = 3.333... 10x - x = 3.333... - .333... 9x = 3 x=3 But according to me, .333... should equal to .4 , isn't it? I must be...

Why does it look like a ripple on a pond instead of a three dimensional object?

So, I was playing around with a couple of voltage multiplier circuits a few months ago, and while optimizing one design, I came up with a pretty neat (not to brag) way of converting a sine wave to a square wave by using transformers in a completely different way than normally. A little while...

Homework Statement This is not really a homework problem but I wanted to figure out how to derive the equation for a strained eye which is $$ M= (N/f) $$ where N is the object distance from the normal near point, and f is the focal length of a magnifying glass. But then, this is for a relaxed...

So folks, there is this "green cat of Bulgaria". I see it on Google images. How does one explain this? Someone dyed the cat? The pictures are fake? It fell into some chemical? The cat is a mutation or an omen? The cyan color is very strange. I don't know about this.

why does it spin?https://www.dropbox.com/s/4ctfyymbp1i0rhp/Photo%20Feb%2003%2C%2013%2006%2032.jpg?dl=0

Greetings from NZ...I'm a new member and a physics luddite. In 2008 I had a close encounter with what I eventually found out was Ball Lightning. I find it hard to believe that here we are 2015 and still no solution to this phenominon. Are there any researchers out there currently working on...

Several theories try and explain consciousness from a quantum perspective. Most notoriously the Penrose-Hameroff Orch OR hypothesis comes to mind, but there are others by Henry Stapp, Giuseppi Vitiello, and Gustav Bernroider to name a few. The consciousness philosopher David Chalmers has...

Hi! I saw something on my lecture notes that I don't really understand. It reads "Rare gases have filled s and p-sub-shells, which leads to a spherically symmetric charge distribution. Since electrons are indistinguishable they take on a common wavefunction. The point is that this results in a...

why the bottle shrinks?(1)I know according to Gay lussac law Temperature ∝ pressure, as temperature decreases pressure also decreases .But why bottle would shrink if pressure decreases,because decreases in pressure just mean molecules are not hitting that fast. (2)And if bottle shrinks it's...

Does anyone happen to recognize the phone or pc accessory displayed in the attached pics? It looks like a mini domed-camera or a glass bead, tethered to a cord. On its flat side there's a peel-off sticker, like a piece of two-sided tape, to mount the thing on a flat surface. The cord plugs into...

Hello everyone. I have to describe is the Severn Bridge, a suspension bridge spanning the River Severn and River Wye in England. I have found almost all the measurements, except for one: the sag span. I could only find the sag ratio (1/12) but I need to convert this ratio to meters. Can anyone...

Have fun: Art, Ben, Cam, Dan and Ern each added a different kind of room to his house. Each added room can have a width of 10, 11, 12, 13 or 14 feet, and a length (not necessarily respectively) of 15, 16, 17, 18 or 19 feet. From the clues below, determine the kind of room each man added as...

Hello all. I am not an electrical expert here, just know enough to wire basic things at home (i.e. switches, outlets, etc)...so please be kind. My situation is this. We recently bought a new house and have found a couple of mysteries. The biggest one is that there are several electrical...

Hi everyone, I read in a first year textbook (K&K) that the reason why "gravitational mass is proportional to inertial mass" is a big "mystery"... Can someone please explain why this is a mystery? Thanks

Found one article saying it is possible to reverse poles of permenant magnet using coiled wire wrapped around magnet, but nothing about the possibility of temporarily reversing or even temporarily weakening the magnetic field.. if there are any magnetism connoisseurs out there..

Homework Statement Find f°f Homework Equations f(x)=x/x+1 The Attempt at a Solution \frac{x}{x+1} divided by \frac{x}{x+1} I got \frac{1}{x+1}+1 but I know the answer in the book is \frac{x}{2x+1}. I'm not sure how the book arrived at that answer.

Empty a can of Vienna Sausages, except for the broth that remains. Leave it out, in the upright position, for your cockroaches. You will find that they crawl into the can and die, and so many victims there are. The question is why. They apparently do not attempt to crawl out because there are...

My favorite new geographical shape is now, drum role please...the Monkey Saddle. When I looked at it initially, I thought right away I knew why it was called a Monkey Saddle. The shape (to me) just kind of looks like a monkey. Particularly, you can see the two ears on the side. The downward...

Hey all, As the title suggests, I've found some recurring structure on an SEM image and I can't for the life of me figure out what it is. I took the image this morning. Here she is: http://i.imgur.com/nFuBsW2.png Here's a larger, more zoomed out and higher res version. A few more of...

A bottle has a mass of 33.00 g when empty and 97.55 g when filled with water. When filled with a mystery fluid the mass is 84.02 g. What is the specific gravity of the mystery fluid? Hopefully helpful equations: p = m/v (p = density, m = mass, v = volume) SG = 1000p Attempt: I'm...

My A level Chemistry textbook defines Lattice Energy as "the enthalpy change when 1 mole of an ionic compound is formed from its gaseous ions under standard conditions"; a definition which I can't fully grasp because of the "standard conditions" part. How can gaseous ions exist under standard...

Because I am a little tired to think... For where does the mass difference between the W and Z bosons come from?

This is amazing. Dieudonne, Erdos, Atiyah - it's mathematical heroes galore. (heart)

Hello, Hope someone finds this a challenge. Thought it would be a snap to find out, goggled it, nothing. Weeks later have not found one person in the world that knows of one example of how fast coil springs release. Just talked with Hyperco a major manufacturers head engineer, he...

Why is the initial current through the inductor 20A? Surely the current splits at the junctions?

Hello, I read an article a long time ago and it mentioned a mystery in how we create and use energy. It listed the cycle of ADP to ATP, all the steps, but for one of those steps it said something like in practice this happens much faster than what we know to actually be possible. This...

The door hinges inside my place are pretty old; I'd guess a few decades though I don't have any way of knowing for sure. I do have experience with metal on metal rubbing and degradation. So I wonder, why can door hinges open and close for a long time, and not wear away? I don't think I've...

Observing which slit a photon or particle goes through in the two slit experiment results in the formation of a diffraction pattern instead of an interference pattern. Were Feynmanns remarks about this made by referring to the classical experiments where there is high illumination or to the...

If all the matter in the universe was compressed into single tiny space before the big bang, where was it? I mean "Out past Orion" would do.

I understand that mass isn't weight. When I look up "what is mass?", I come across all kinds of videos explaining the difference between mass and weight, but that is not what I am looking for. I'm trying to understand the concept of mass, fundamentally, because it doesn't really mean anything to...

I am currently confused... I read that we don't know yet where does the proton spin come from. But I wonder... 1) Doesn't the proton have effectively 3 quarks of spin 1/2 (I said effectively to leave out the quark-gluon sea within the proton)? In that case, 3 spin 1/2 particles can't be added...

Here's something that has been bugging me for decades. Well I keep forgetting about it thankfully, but I've never really been able to answer it. Why is Pi actually the value that we have for it and not some other number? If the ratio of a circle's circumference to its diameter was any...

Hi everyone, First I want to say that I hardly know anything about advanced physics, and I'm just looking to ask something that I've been thinking about for a while. So I'd also appreciate if you kept the explanation somewhat understandable :P Anyway, here's my question: If light from...

Hi - When an engine uses chemical energy to move a vehicle, the fuel loses mass in the conversion, so that momentum (mv) stays the same before and after the acceleration? If this is true, then we convert mass to velocity all the time, while keeping mv constant, right? Where does velocity...

Hello, I have this integral here: \[\int e^{\sqrt{x}}dx\] and I wanted to ask, why can't I treat it like I would treat this integral: \[\int (3x+5)^{5}dx\] In which I would integrate as if g(x)=3x+5 is a normal x, and then divide by the inner derivative ? I tried it with the upper integral...

I'm sitting on a bench in a park. I exert a force of H Newtons and the bench exerts a reactive force of H Newtons back and we're in equilibrium. Next to me a 10ft tall short-faced bear sits on an identical bench with B Newtons. After about 20 seconds the bench gives in and collapses. I...

Hello, I am confused about voltage division. In reference to the circuit on wikipedia, I don't understand why Vout = R2/(R1+R2)Vin and not R1/(R1+R2)Vin. The current goes through R1 first and has a drop over that resistor, not R2. https://en.wikipedia.org/wiki/Voltage_divider#Resistive_divider

My apologies if this has already been covered. I did a search, but couldn't come up with anything. My question is this. If you come across a random transformer with no markings, how can you tell it's watt rating? I have acquired several MOT's, and wish to use them in a DC arc welder. I...

In the picture, I have the question and the Saha Equation. I have all the correct answers for all the variables and constants on the right side of the equation, and I've done the calculation twice, and I'm getting an answer of 1.56x10-28 That is equal to the left side, which is NII/(NI+NII). NII...

What seems like a simple fix turns out not to be so simple. Question, I have an old mill with a waterwheel. The shaft turns at 100 RPM. We figure based on what was there a minimum 300HP so 300 x 746 watts per HP, this has the potential to generate 223.8 Kw’s of electricity. A 72 pole...

First of all, Happy Thanksgiving to you all! Now, my question: I'm on Earth viewing through a telescope. I observe a car in outer space, traveling roughly at right angles to me (i.e., across my scope's field of view, let's say left to right). That car, a 1956 Chevy (irrelevant, but my...

Don't wait until the last minute to buy a big Butterball fresh turkey. For some unknown reason the fresh turkeys failed to gain weight. "I don't buy the For whatever reason" bit. It has to be a lot more serious than...

Homework Statement If ##|G| = p^2## where ##p## is a prime, then ##G## is abelian. 2. The attempt at a solution The book my proof gives is confusing at the very last part. Suppose ##|Z(G)| = p##. Let ##a\in G##, ##a\notin Z(G)##. Thus ##|N(a)| > p##, yet by Lagrange ##|N(a)| \ | \ |G| =...

I know the power spectral density, PSD, of noise is: \frac{N_{0}}{2} from where do we get N_{0} ? Is that the RMS value of the noise? Is it related to noise power and noise temperature as in the following: N=kTB, where k = Boltzmann’s constant, T is noise temperature, and B is...

Hi all, i was pottering away at work yesterday and realized just how little i truly understand about vacuum! So i have a question, i have a piston in a cylinder, the piston is fully in the cylinder so there is very little air space and the cylinder port is blocked off, the piston has an area of...

https://www.physics.harvard.edu/uploads/files/undergrad/probweek/prob90.pdf https://www.physics.harvard.edu/uploads/files/undergrad/probweek/sol90.pdf This is the puzzle I am trying to understand. Does anybody has any idea how the table on the top of the second page i being deducted...

HI all, recently I have gotten a sore and swollen throat and multiple itching red spots that I've itched raw. they are widespread and not close together they look like spider bites. I've recently slept on a mattress that hasn't been washed in a while. It feels like things are crawling under my...

Sodastream sells a device that will charge a 1 liter bottle of water with CO2 gas so you can drink fizzy beverages. I always use 40F cold water from the fridge to fill the bottle, and seal it tightly, but I find that after only 1-2 days 90% of the fizz is gone, a much shorter life than fizz...