# Kedas

Senior Members

695

1. ## Why is a falling column of water thinner at the bottom?

You could prove it with some math but basically it's just because the speed of the water is increasing while it's falling and since the flowrate is the same for every hight the volume at that hight must decrease. The cohesion force makes sure the water stay's close together in the cases that it doesn't then there will just be (more) air between the water drops. One more thing if it really would be ONE column of water released at one time and falling (not streaming water) then all molecuse would fall at the same speed and you wouldn't have this effect.
2. ## Adding 2 speeds close to c

yes, I got it backward. What happens stays the same it's when it happens that changes. Thanks for the explanation This is a much more understanding way of calculating it than the simple formula. Test When Z travels back from YY to Y at the same speed of 0.866c (according to Y&YY). Then Earth will see Z at a speed of 0.5/((1.155-0.866)*2)=0.866c right? This means that the speed of Z will be the same for Earth, Y and YY.
3. ## Corrupted pictures

Maybe the card was formated wrongly/different than what the camera expected. Not sure if they can be recovered. (you mean USB connection right)

5. ## CD Quality & The Human Ear

A lot more information is lost/changed due to the music installation (including speakers) BTW it's half the sample rate that has to be 'well above our perception'.
6. ## Adding 2 speeds close to c

OK I have two clocks in sync both will give a light flash at the same time. I put them at both ends of a train. The train moves fast the flashes go off, I see them go off at the same time and those at the train also see them go off at the same time. But since the train moved after the flashes went off the light doesn't meet in the midde of the train. And on the train light also moves at c so the flashes do meet in the middle from there point of view. But how does that effect my speed measurement from earth? Even with length contraction I still get more than 0.123c edit: the math the difference is z.(1-y²)/(1+y.z) with z speed Z relative to Y and y speed of Y relative to X y and z are factors of c in my case it's 0.866*(1-0.866²)/(1+0.866²)=0.123 or 0.866/7
7. ## Adding 2 speeds close to c

Why would Clock YY lag behind clock Y? They are in the same reference frame so if it are two or just one big station it should be the same from earth. I want to know how to get to 0.123c taking all effects in account. I'm measuring their speeds with a laser on earth and Y is measuring the speed of Z with a laser on Y.
8. ## Adding 2 speeds close to c

three objects X=earth, Y=space station, Z=space craft The space station Y travels at 0.866c away from earth X, at the space station they launch a space craft Z that is also moving away from Y at 0.866c. now what does earth see: Y at 0.866c Z at somewhere between 0.866c and c From earth point of view this means Z is barely moving away from Y but at Y they see Z moving very fast away in the same way that X sees Y. So how can Z be fast and slow at the same time. The only explanation is that due to the fact that time at the space station Z is going much slower it's only from their point of view that it's going that fast. 1 second on the space station is two seconds on earth. So the speed of Z in reference to Y of 0.866c is only 0.433c seen from earth. But the sum of 0.866c and 0.433c is still faster than c and that's not possible. Z from earth should be 0.9897c or 0.123c faster than Y (not 0.433c) So what did I forget? space contraction?
9. ## Adding 2 speed close to c

see other thread (delete this one, thanks )
10. ## Debunking the Butterfly Effect

I don't think this is true but it's obvious that not all small changes lead to a big change. (we don't have enough space for all those tornados) Otherwise doesn't that mean that anything you do can't have a big impact on the future of the world since the 'main path' is defined by attractors. With other words the end result and the path is predefined or if Einstein died in an accident at young age someone else would have replaced him.
11. ## Magnetism and kinetic force

What do you mean? BTW pressure=force/area, ignore that 'hydraulic lifts' sentence. hydraulic lift: a small force is put on a small area so the force would be bigger at the other end were there is a big area. (pressure is the same for both area's)
12. ## Artificial Intelligence

No, it would be: "I move using my legs, If you damage your legs, moving is likewise impared"?
13. ## Thermo Energy

Reusing those heat losses isn't easy and if possible not cheap. That is why they are concentrating on reducing the heat losses instead (increase efficiency, isolation if allowed/possible.) A light bulb is one of the worst examples almost all the used energy is heat loss and only a smal bit is light energy. But this will help a lot in the future: White LED to replace light bulb http://www.livescience.com/technology/051021_nano_light.html
14. ## Magnetism and kinetic force

I was curious myself so: found the answer on this page:http://physicsweb.org/articles/world/17/1/6 Also interesting to know we are talking of magnetic fields of 1T to 5T.
15. ## Magnetism and kinetic force

first question: Yes. second: Yes, it should, how much? I don't know. Are you planning to build a fusion reactor?
16. ## The Lorentz Transformation, Speed & Location

When you have the speed & location info at time t from all objects that observer A is seeing. Is it then also possible to calculate what observer B would see at time t? 1) if A and B do not move relative to each other 2) if A and B do move relative to each other Did anyone wrote a 4D program that can calculate what observer B is seeing (matlab?) ----------------------------- some info links about Lorentz Transformation http://hepth.hanyang.ac.kr/~kst/lect/relativity/x146.htm http://home.usit.net/~cmdaven/cmdaven1.htm
17. ## The Ultimate Gravity Theory

So the (gravity) force is present after alignment of the 'bar magnets' So what you are saying is if you put mass A & B at 1meter distance they will have a certain attractive force but if I disturb the alignment of A and/or B with a third mass C the force between A & B will change significantly???
18. ## Measuring vibration

if vibration measuring devices don't have what you are looking for then nothing will. http://www.korins.co.kr/davis/m/l.pdf
19. ## Cleaning your blood by donation.

There were some news messages recently that the amount of toxic products in our blood is rising. (some say risky, some within tolerance) I was thinking if blood donation would help reducing ANY unknown toxic in your blood. I did some simple math You can give about 10% of blood with pauzes of minimum 16weeks. 0.9^6=0.53 so in about 6*16weeks or 2years I would be able to cut the percentage of toxic producs in my blood in half. This is obviously assuming that there are no new producs added during that time and that they are present in my blood. Is the body itself cleaning your blood in some way? (I mean products that aren't suppose to be there, like some metals: aluminum, lead, etc..)
20. ## Humanity's Blind

Well you basicaly answered your own question at least that one. It's designed for us to like it it's not designed to be healthy. To much the same thing is never good even if your brain likes the product.
21. ## Voltage

In theory you don't have a solution. your voltage is 0*inf. In reality it wil be lower than your open circuit e.m.f. the value will depend on those resistors. (which wire is used, which battery is used)
22. ## Voltage

In theory you would create an infinite current. In reality the source is an ideal source with a resistor. and the wire wil also be a resistor. If you add these resitors your circuit will make sense again.
23. ## Conservation of information law

some articles about it http://arxiv.org/PS_cache/gr-qc/pdf/0108/0108010.pdf http://www.sciencenews.org/articles/20040925/bob9.asp Found some other but the fact that a lot of them contain 'intelligent design' isn't really a good sign that it's physics.
24. ## Conservation of information law

How to prove or disprove this 'law' if you can't calculate/determin the amount of information?
25. ## Is taking antibiotics bad if you aren't sick? (eye problem)

The title is a bit simple but it isn't that simple: The history: I'm Nearsighted (near is about 20cm for me) but the last years (I'm 32). My glasses can't totally correct my sight back to good vision. (never got perfect vision) Other glasses don't help and they can't find anything wrong (except that I can't see very well with my glasses) They also looked in my eyes and one said it's like a little infected while the other says no it isn't. The questions: 1) Is it possible to have a light infection in both eyes for a long time? 2) If yes could it be they didn't saw it (because not easy to see) and it's the reason of my vision becoming worse? 3) Would taking antibiotics solve this problem? (I haven't taken antibiotics in a long time, more than 10years) Would it be harmfull as experiment to see if that was the reason? Or is it impossible to know which antibiotic and how much you have to take? Thanks
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