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The last mission to the International Space Station, I heard one of the astronauts had to do a space walk to fix the bog.
Does that mean the International Space Station has got an outside toilet?
simonfbarnes - MemberYou need to focus on the word "proportionately".
yeah but when I do that it seems to say that St. Paul's is bigger than the universe
O.K. - I am proposing two space/matter scenarios.
1: a sterile St Paul's cathedral interior into which has been placed a speck of dust.
2: the universe in which matter exists.
Measure the proportion of matter in the cathedral to the space in which it exists (the walls of the cathedral are the limit of measurement).
Measure the proportion of matter in the universe to the space in which it exists.
As a proportion of scale, the measurement of the speck in the cathedral is greater than the measurement of matter in the universe by the number "billion billion..".
So is the universe actually [i]inside[/i] St Paul's cathedral? That's well strange. Like that bit at the end of Men In Black II when he opens the door and the whole universe is inside one left-luggage locker in a gigantic railway station in another larger universe...
First man to (allegedly) fly around the moon, whilst Neil Armstrong and Buzz Aldrin (allegedly) landed on it was Michael Collins. Not the Irish one though.
it's the final frontier, don't you know...
Any photon which emitted from the big bag and is still travelling has been travelling for no time at all, from it's experience.
Assuming it hasn't slowed down.
Photons don't speed up or slow down, that's kind of what they do, tear arse around at the speed of light.
Photons don't speed up or slow down, that's kind of what they do, tear arse around at the speed of light.
The "speed of light" varies depending on the medium it is travelling through.
http://en.wikipedia.org/wiki/Variable_speed_of_light
Q. Who was the last man to walk on the moon?
A. Eugene Cernan
Q. What were the last words spoken on the moon
A. "Let's get this mother out of here"
Woppit's analogy (as it will become famously known) is a funny one because whilst it's easy to comprehend a speck of dust in St. Pauls, it's not easy to comprehend a billion billion billion to the power of a trillion (or whatever)
so it tries to simplify a concept using things that are imaginable, then blows it out the water with unimaginable numbers
or is that the point?
.
space is confusing
The varying speed of light cosmology, mostly proposed by Jean Pierre Petit, has no substantial evidence for it as is regarded as merely a concept though.However....It would require a rewrite of much of modern physics, to replace the current system which dependent on the constant c. which has been functioning quite well for quite some time now 🙂
A photon - as you know - is an electromagnetic (EM) wave.Its energy is described by e = h. n in a quantum of energy. All EM waves travel in the vacuum with the speed of light. A photon is a form of energy and
results from transformations of another forms of energy.
When the photon appears it behaves like all EM waves.It does´t need to be accelerated. All bodies emit EM waves,even a peace of ice. The question concerns more on the frequency. If you see the light - visible light - it covers a range of wave length between 400 and 700 nanometers.
frequency. If you see the light - visible light - it covers a range of wave length between 400 and 700 nanometers.
Waves do not need to be accelerated or decellerated. Particles
do, but we are talking about wave-photons, aren´t we ??And - besides of that - photons are generally regarded as particles with zero mass and no electric charge...
As physics stands currently, photons do not accelerate or decelerate no matter what wiki says.:) although they possibly and that's a really very big possibly in the future.
Other possible pub quiz answers:
Thomas Jerome Newton
Jeffrey Hunter as Captain Christopher Pike in 1964
Barbarella (1968)
Twiki and Dr. Theopolis
The Tempest
H.G. Wells
That should cover it.
jahwomble: isn't [i]c[/i] specifically the speed of light in a vacuum? It is a top speed, rather than the only speed.
If you can't slow it then what were these guys doing in 2000?
http://news.bbc.co.uk/1/hi/sci/tech/655518.stm
http://focus.aps.org/story/v3/st37
"We know that light can be slowed to a modest extent in refractive and transparent media, for example water and glass, to velocities typically a factor of 1.5-2.0 times slower than c. But there is a limit to how much light can be slowed in normal optical materials, because the larger refractive index associated with slower propagation is inevitably accompanied by increased light absorption."
-- http://www.nature.com/nature/journal/v397/n6720/full/397559a0.html
In a relatively short amount of time free space in a house can be filled with bike bits 😆
thepurist - Member
@clubber - and there is also a version of STW where there IS only one tyre for....(and one where weeing in shoes is the ultimate form of politness, and one where televised bomber combat is the biggest national sport)
This is FACT (based on an infinite universe, again)
That's slowing the passage of light from a to b, not photons.When light enters a material, photons are absorbed by the atoms in that material, increasing the energy of the atom. The atom will then lose energy after some tiny fraction of time, emitting a photon in the process. This photon, which is identical to the first, travels at the speed of light until it is absorbed by another atom and the process repeats. The delay between the time that the atom absorbs the photon and the excited atom releases as photon causes it to appear that light is slowing down. in simple terms, the photons "bump" into the atoms and "bounce" off again so the light appears to travel slower, but the actual photons are not traveling any slower. They are just taking a more circuitous route from a to b
BigDummy - MemberSo is the universe actually inside St Paul's cathedral? That's well strange. Like that bit at the end of Men In Black II when he opens the door and the whole universe is inside one left-luggage locker in a gigantic railway station in another larger universe...
No. The one is simply an analogy of the other, for the purposes of proportionate comparison, to illustrate how much space there is, compared to matter. In the universe.
in space, no one can hear you scream
Ah got ya. Thanks jahwomble.
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Silver Surfer aka Norrin Rad of planet Zenn-La.
Became first Herald of Galactus when he sacraficed his normal life and the love of Shalla-Bal, in order to save his home world from the planet devourer. Wields the power cosmic, which is transmitted through his board.
Catch phrase, . . "This cannot be?"
It goes on, but those are the basics . . . hey ya never know . . ?
S'ok 🙂 I love this stuff.......
... not forgetting of course, that "space" is probably just "dark matter" rather than an absence of matter. I suppose that, if you perceived the dark matter as matter and the matter as space, you'd be a bit pushed to get around. Even with the proper tyres on...
What do you want more at the end of a relationship rather than the beginning?
Space
Measure the proportion of matter in the cathedral to the space in which it exists (the walls of the cathedral are the limit of measurement).Measure the proportion of matter in the universe to the space in which it exists.
one billion billion billon to the power of a trillion = (10^18)^1,000,000,000,000 = 10^18,000,000,000,000
estimated density of the universe =~ 1 atom hydrogen per cubic metre = 1.66 * 10^-27 kg/m^3
assuming a grain of dust to be one milligramme and St. Paul's to be a one hundred meter cube gives a density of 10^-6/10^6 ie 10^-12 kg/m^3
so the actual density ratio is 10^-12/( 1.66* 10^-27 ) = 6 * 10^14
headfirst - MemberWhat do you want more at the end of a relationship rather than the beginning?
Space
Or Sex
Sorry, that should have been a [i]thousand[/i] billion billion billion etc...
Oops. 😉
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Chickens rely on gravity to allow food to 'roll' down their gullets - humans and other animals have 'peristalsis' - the muscular movement propels food into the stomach.
Therefore, if you want to kill a chicken, take it into space, where the minimal gravity effect will cause it to starve.....obviously...
DrP
toys19: Personally I'd want sex more at the beginning rather than the end...
The OP is going to be very disappointed when he finds out the pub quiz topic is actually [i]"Man in [u]Spaced[/u]"[/i], Simon Pegg.
one billion billion billon to the power of a trillion = (10^18)^1,000,000,000,000 = 10^18,000,000,000,000estimated density of the universe =~ 1 atom hydrogen per cubic metre = 1.66 * 10^-27 kg/m^3
assuming a grain of dust to be one milligramme and St. Paul's to be a one hundred meter cube gives a density of 10^-6/10^6 ie 10^-12 kg/m^3so the actual density ratio is 10^-12/( 1.66* 10^-27 ) = 6 * 10^14
Ah,so thats where my pesky little Hope pad pin security clip has gone....
No wonder I can't find the ****er!!
GrahamS, if the topic was Spaced I'd be laughing. Most of this is way over my head tbh.
Intrigued by the reference to the Tempest.
Forbidden planet?
Top marks jahwomble 😀
Ta 🙂
It's one of the best clubs in Ibiza, possibly the world, also the bird who does the live sax ( yes it's not a typo) makes abby from the zutons look as sexy as ya mates nan!
All furniture in space was purchased at Habitat, apart from the Russian Space Station, Tid. That was purchased at Ikea.
All furniture in space was purchased at Habitat, apart from the Russian Space Station, Tid. That was purchased at Ikea. And so was this computer(oops)
I am sure the speed of light does vary depending on the medium. The slowing down of light mentioned there is just that - slowing down. The light is not being absorbed and re-emitted. It's how refraction works afaik.
And damn the second poster who posted the Adams quote I was going to. Once again he hit the nail on the head with the best description. A bit like the R unit of speed measurement.
Right.. a pub-quiz style space fact. Umm... related to people IN space, right? Umm... Sputnik was launched in 1957, and broadcasted a beep. The Russians tried to tell the Americans that it was coded spy data, but it was just a beep... the gold record on Voyager 2 contains, amongst other things, Beethoven's 5th, Brandenburg concerto no 2 and Johnny B. Goode by Chuck Berry.
Sputnik 2 carried the first living thing into space, a mongrel dog called Laika, but they didn't design it for re-entry so the dog was also the first casualty.
"I am sure the speed of light does vary depending on the medium. The slowing down of light mentioned there is just that - slowing down. The light is not being absorbed and re-emitted. It's how refraction works afaik."
Yes it does vary in a sense but the speed of the the protons contained within the light doesn't.Refraction simply changes the a to b route of the protons so that they seem to take longer to get there.This is exactly how refraction works, the refractive index of the material is a measure of how much it diverts the protons effectively,But protons will always move at the speed of light regardless of the medium
So yes, light can seem to travel slower, but it actually is just being diverted and thus takes longer to reach it's destination.
Neil Armstrong didn't say anything about "Mr Gorsky" or any other neighbour while he was in space 😐
I seem to remember deriving from the wave equation the formula that says that the speed of light is equal to the reciprocal of the permitivity of free space multiplied by the permiability of free space. Free space being the key word there; permiability and permitivity are different for different media.
When talking about transmission of light one usually doesn't talk about photons. Photons for interactions with other particles, waves for transit.
Black holes are more numerous than you would think...
There's one under every fridge freezer in a mountain bikers kitchen and thre's one in every washing machine, although these are quite weak and collapse on themselves after devouring a single sock....
I suggest you read up on the particle/wave duality of light and photons. I've already posted the stuff below once already today and really can't be arsed going through it all again.
A photon - as you know - is an electromagnetic (EM) wave.Its energy is described by e = h. n in a quantum of energy. All EM waves travel in the vacuum with the speed of light. A photon is a form of energy and
results from transformations of another forms of energy.
When the photon appears it behaves like all EM waves.It does´t need to be accelerated. All bodies emit EM waves,even a peace of ice. The question concerns more on the frequency. If you see the light - visible light - it covers a range of wave length between 400 and 700 nanometers.
frequency. If you see the light - visible light - it covers a range of wave length between 400 and 700 nanometers.
Waves do not need to be accelerated or decellerated. Particles
do, but we are talking about wave-photons, aren´t we ??And - besides of that - photons are generally regarded as particles with zero mass and no electric charge...
It's got nothing to do with acceleration. Acceleration is what happens to things with mass. The energy of a particle is related to its speed, but the energy of a wave is related to its frequency.. which is related to its speed and wavelength..
So if a wave enters a medium with different permiability and permittivity then the speed of the wave will slow... but because nothing is being accelerated or decelerated here the energy of the light is not changing so the wavelength is simply shorter. That way when the light emerges the speed goes back up again as it would do if you shine a beam of light into a piece of glass. When the beam emerges it has the same velocity as when it went in.
I did read your original post but you didn't provide a proof of why the speed of light WOULDN'T vary in different media.
Maxwell's equation however shows how it DOES vary:
c = 1/??0?0