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21
General Science / Vaccine for Parkinson's?
« Last post by thedoc on 20/08/2014 13:08:34 »
Initial results are in for the worlds first ever vaccine for Parkinson’s disease, and it looks promising.
Read a transcript of the interview by clicking here
or Listen to it now or [download as MP3]
22
General Science / How can you decrease your liklihood of Alzheimer's
« Last post by thedoc on 20/08/2014 13:08:34 »
Up to a third of cases of Alzheimer's disease could be preventable by being fitter and healthier, new research suggests...
Read a transcript of the interview by clicking here
or
23
Radio Show & Podcast Feedback / Brain Hype or Help?
« Last post by thedoc on 20/08/2014 13:08:34 »
Drugs to make you smarter, helmets to induce creativity, brain scans to convict people and mind findings in military warfare.
Read a transcript of the interview by clicking here
or Listen to it now or [download as MP3]
24
Technology / Re: Making a water whirlpool ?
« Last post by vivian maxine on 20/08/2014 11:25:07 »
Refill your pool with superfluid Helium, and give it an initial stir?

Pull the plug?
25
Just Chat ! / Re: Punning is hard(ly) work! Groaning aloud here?
« Last post by Don_1 on 20/08/2014 09:14:38 »
Today is National Aviation Day.

So we should all get off to a flying start, not just try to get by on a wing and a prayer.

Don't expect to eat something fancy when you're flying because it's plane food.


I had the baguette with a jumbo sausage.

Tea & coffee was served in a china cup on a flying saucer.
26
New Theories / Re: thrust does not work in space
« Last post by alancalverd on 20/08/2014 07:03:05 »
Have you ever fired a rifle? The recoil force is exactly the same whether you fire it under water or in air. Recoil force is independent of the surrounding medium.

Conservation of momentum is demonstrated in many ways: billiard balls, "Newton's Cradle", spinning tops and skaters.... and in no case is there any requirement of "something to push against".

Rockets work by conservation of momentum, nothing else. You chuck stuff out of the back and the rocket moves forward so that the net change in momentum is zero.

Interestingly, motor boats and aeroplanes work on exactly the same principle, except that the "stuff they chuck out at the back" happens to be the same ambient water or air that they are floating in, accelerated by the propellor. The difference with a rocket is that you carry the stuff with you as there isn't any ambient stuff to use.

You may have noticed that true space rockets http://www.google.co.uk/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=xpmJJ5zcgCRSRM&tbnid=qpYSfLkBXvNeGM:&ved=0CAUQjRw&url=http%3A%2F%2Fen.wikipedia.org%2Fwiki%2FAriane_(rocket_family)&ei=hkn0U_mDM4TK0QWE7oC4Dg&bvm=bv.73231344,d.d2k&psig=AFQjCNHgZpahKRn9bUN56MEe01OpAWmX0A&ust=1408604919233069 don't have flaps, ailerons or even wings. Have you asked why not? Directional control in space is done by pointing the rocket motor the way you want to go. The fins on the archetypal V2, and on air-to-air missiles, are for directional control whilst the machine is flying in air, which it does for most of the time. 

Ultimately you are going to have to convince yourself. Not difficult. You can buy a model rocket motor, attach it to a spring balance, and fire it in a vacuum jar. Or just watch what happens if you energise an electric bell or a newton's cradle inside a vacuum jar. The absence of air makes no difference to the conservation of momentum.

The problem you will have is accepting that the laws of physics apply equally everywhere. Fortunately for the rest of the universe in general, and pilots and engineers in particular, that seems to be true.
27
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28
New Theories / Re: thrust does not work in space
« Last post by Reality207 on 20/08/2014 02:46:01 »
I have read the objections to this statement and the arguments/logic behind it.
This subject has tormented me since childhood, as it does seem illogical that a rocket can work without resistance to push against.

Take the motorboat out of water and there is no resistance for it to push against.
Take the rocket out of atmosphere and there is no resistance for it to push against.

Ya sure Newton’s law “what you push against pushes back”, well if as in space there is nothing to push against or to push back, how can it be!!

I cannot explain why so many good scientists accept NASA's stories with such faith, but this is not a Conspiracy theory, it is logic.  You must reach and live with your own conclusions.  All I ask is that you don’t blindly accept what you were forced to learn and accept and that you apply logic for yourself.

Further, I ask, as flight controls also require atmosphere to react against and there is no atmosphere in space, logic would also demand that flaps, ailerons, spoilers and elevators would not affect the flight path of a space ship in space as they all require atmosphere passing by them to function.   Flight control - 101. 

Now, realistically if we are to attain propulsion in outer space, logic demands it will have to be done by acting or reacting against something that exists in space.  If we are to attain flight control in space it will also have to be done by acting or reacting to something that exist in space.
I'm sorry but again we don't have that at this time, and no explanation of how thrust works without atmospheric resistance is known or offered.

Sorry Please don't hate me for these thoughts, I share with all due respect.
Offer me a logical explanation of how thrust works without atmosphere to push against.  Tell me how thrust can act or react without resistance.
Please don’t sight the example of throwing a ball standing on a skateboard or while sitting in a chair on wheels, as both of these experiments are conducted in atmosphere.
29
Well you can go either way: either use core or dont, as for core it really is a booster in the electromagnet, what it does is to gather the change of electrons and condence it, focus it. As such, any material with metallic properities can be used, even permanent magnets.

in fact, you can use electromagnetism to turn off the permanent magnet.

But for your guestion, you could use a spring coil as a magnet core and wrap isolated copperwire around it, creating a electromagnet. As long as the material is conductive as the core, it will create electromagnetic field. Copper (actually better conductivity than gold), nonstainless steel (specially one thats marked 1010 steel), aluminium, bronze.... get the full list at http://www.candlepowerforums.com/vb/showthread.php?151197-Electrical-conductivity-of-metals

as long as you dont use glass as a core, you should be ok, coiled wire itself can make electromagnet, tho weaker than solid metal core one. the core does not need to be a block or rod either, you can do laydenic kind of magnet by this way: wrap insulated wire around spring coil that is made of copper, insert a NON conductive material pipe through it (like rubber pipe). At the end of the spring you put it through the pipe, and this acts as your ground wire, goes to - at battery. close the circuit. Ofc, i am not going to tell you how to build the circuitry, But now what you got is a core only at selected lenght at position where you want it.

In computer components, especially at capasitors, they use copper wires wrapped around horseshoe like rings. The magnetic force is at peak at the point, where these horseshoes ends almost meet. This causes electromagnet to be more directional. ofc, eletromagnet is strongest at the point of cores point.
Other way is to build a circuit, that has a capasitor on it (like used in cameras, disposable cameras are good source for the parts. This allows you to build burst electro magnets: surges provide most powerfull blasts of magnetism. Higher power = more magnetism, IF allowed by conductivity of the wire.
So, if you want to lower the magnetism, you may want to:
1. lower the current by limiting the battery power or conductivity through circuit (anode)
2. use nonconductive core

also you can make nonferrous electromagnet:
instructions can be found here: http://www.ehow.com/how_7902302_do-make-non-ferrous-electromagnet.html
Anyways, hope this was any helpfull for you?

Things you want to think while building the magnet.
30
Now to answer the question in as simple a way as I'm able:

Inflation theory says that from a time 10^-36 sec. after the Big Bang to around 10^-33 sec., the universe expanded exponentially.

When people state that this expansion was so fast that it violated the speed limit of light, they are mistaken. While the speed limit of light is 186,282 miles/sec. in our present space/time, there is no law of physics that restricts the space/time itself from expanding at any rate it so chooses.

Because it was space/time that expanded and not a particle within that space/time moving faster than light, inflation violates no law of physics.

You might want to check out Brian Green on Wiki, he is one of the leading authorities on the subject.
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