Question of the Week - Old Version

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #50 on: 07/10/2003 02:16:53 »
ANSWER TO "WHY DO PEOPLE HAVE DIFFERENT COLOURED SKINS ?"
 
Itís all down to a substance called melanin, the stuff that suntans are made of. The body produces melanin, which is a dark brown colour, to protect us from the sun because melanin stops harmful ultraviolet rays that can cause sunburn and skin cancer. People with dark skins naturally make much more melanin than fair-skinned people and thatís why their skin is browner. Most of these people have ancestors from hot countries where there is a lot of strong sun and so they have their own natural sun-block. Scientists think that our ancient ancestors came from Africa and all had dark skins to protect them from the sun. But, over thousands of years as they migrated out of Africa to inhabit colder countries, it was no longer an advantage to have a dark skin because there was less sunlight, so people lost their natural sun-protection and became fair skinned.

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #51 on: 07/10/2003 02:18:17 »
This week's question of the week was suggested by Tom (Nilmot)

WHY CAN YOU SOMETIMES SEE THE SUN AND MOON IN THE SKY TOGETHER ?

Have a go below...answer next week.

TNS

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Offline Donnah

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Re: Question of the Week - Old Version
« Reply #52 on: 07/10/2003 23:26:48 »
Why wouldn't you be able to see them both?  The sun emits light and the moon reflects that light.  It just depends on where they are relative to the observer's field of vision.
"Remember, if you ever need a helping hand, you will find one at the end of each of your arms." - Audrey Hepburn

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Offline chris

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Re: Question of the Week - Old Version
« Reply #53 on: 08/10/2003 01:00:06 »
Quick comment to Bezoar in relation to her remark about melanocytes - yes you are definitely right. The melanocyte density is equivalent in black and white people. However, the expression of melanin and the cellular environment differs to make black people produce more melanin overall.

Chris

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Offline Qing

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Re: Question of the Week - Old Version
« Reply #54 on: 08/10/2003 09:52:43 »
usually,when we see the sun and the moon appear in the sky together will either be break or dawn except when there is a solar or lunar eclipse,so what I am thinking is that it depends on the angle the earth "lays"and the orbital it is "running" aroud the sun and also how the moon orbiting around the earth.besides this,I guess there must be something to do with at which latitude you are standing and observing from. I vaguely remember when I was in school I was taught that the orbital of the earth travelling around the sun is not horizontal,it's kind of oblique,a few degrees to the horizontal.
These just pure guesses,and don't know how to explain it clearly[:(]hope you can all understand me.

Qing
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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #55 on: 17/10/2003 13:37:49 »
HERE'S THE ANSWER TO LAST WEEK'S "QUESTION OF THE WEEK", SUBMITTED BY NILMOT (Tom Lin)

The appearence of the moon in the sky depends upon the position of its orbit. There is no reason why the moon and sun should not appear together in the sky since they are totally independent of each other. The moon orbits the earth and the earth orbits the sun. Therefore sometimes the moon coincide on its orbit with the rising of he sun and hence the two will appear in the sky together.

This is precisely how an eclipse occurs, only on this occcasion the path of the moon crosses the path of the sun. But the two bodies are still in the sky at the same time.

I think most people seemed to get that one right. Good question though. By an amazing co-incidence a lady phoned the radio show a few weeks ago with the same question !

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #56 on: 17/10/2003 13:41:08 »
THIS WEEK'S QUESTION OF THE WEEK

"HOW DO WE KNOW HOW HOT THE SUN IS SINCE WE CAN'T GO AND MEASURE IT ?"

TNS

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Offline Ians Daddy

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Re: Question of the Week - Old Version
« Reply #57 on: 17/10/2003 15:01:01 »
Guessing....will take a better stab at it later after some thought.
Guess: Temp. x Distance

I know that's probably wrong, but I'll build on it.
 

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Offline Quantumcat

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Re: Question of the Week - Old Version
« Reply #58 on: 17/10/2003 22:19:43 »
colours - the material of anything burns at different colours depending on the temperature and what the materials are

we know what the materials are from the spectrum

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Offline cuso4

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Re: Question of the Week - Old Version
« Reply #59 on: 22/10/2003 17:17:30 »
Is this called the BLACK BODY RADIATION? Never mind me if I'm talking rubbish.

Angel
Angel

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Offline tweener

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Re: Question of the Week - Old Version
« Reply #60 on: 23/10/2003 04:49:35 »
quote:
Originally posted by cuso4

Is this called the BLACK BODY RADIATION? Never mind me if I'm talking rubbish.

Angel



Black Body Radiation is correct.  The spectrum of the radiation given by any body that has a temperature above absolute zero has a certain shape and the location of the peak and the distribution change with temperature.  So, it doesn't matter what the body is made of, you can measure its temperature by measuring the radiation it emits.

The universe is emitting radiation in the microwave range (wavelength of several cm) which gives it a temp of about 3 degrees Kelvin.  Red hot steel is emitting in the red end of visible light (wavelength about 700 nm), and the Sun emits in the visible and higher (wavelength around 500 nm) with a surface temperature of 5800 K.  The core is about 15 million degrees K.

To find out what it is made of, again measure the radition, but look for other things.  Each element and molecule will emit or absorb radiation strongly at certain wavelengths.  Looking at the spectrum, these appear as bright or dark lines.  The selectivity is caused by the quantum nature of the electrons in the outer part of the atom or molecule and how the electrons can behave in their orbits. Each element and molecule is very distinct.  Because they are all bunched together, the lines are spread out because of all the collsions the particles are undergoing.

Another book, but this is fun!

John

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #61 on: 27/10/2003 22:45:51 »
Since John explained it so beautifully, there is virtually nothing I can add to the answer to last week's question "How do we know how hot the sun is?". The answer is indeed by spectroscopy - the colour of the sun indicates its surface temperature. Some experienced steel workers can predict, to within 1 degree accuracy, the temperature of their steel, just by looking at its colour.

Well done everyone.

TNS

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #62 on: 27/10/2003 22:47:30 »
Here is this week's Question of the Week :

"HOW DO BACTERIA BECOME RESISTANT TO THE EFFECTS OF ANTIBIOTICS?"

Have a stab below...

TNS

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Offline Ians Daddy

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Re: Question of the Week - Old Version
« Reply #63 on: 27/10/2003 23:11:16 »
I know it's layman and probably sounds silly, but my guess is like a military strategy. Like keeping your friends close and your enemies closer. They bond to the antibiotic and learn all they can of it's make up. They record a memory of it and restructure to accomidate it. At that point, they are immune because they are somewhat related. Just like snake venom used as the anti-venom. I really don't know, I just thought I'd take a guess. I figure I've got 50/50 odds of being right or wrong.

Just a thought.
 

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Offline bezoar

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Re: Question of the Week - Old Version
« Reply #64 on: 28/10/2003 04:44:00 »
Sounds like a layman's description of mutation to me.  Pretty astute. Then too, bacteria like to exchange DNA when they sit together side by side.  I hear it's only a matter of time before we get a Vancomycin resistance staph strain, from exchanging DNA with the Vancomycin resistant enterococcus.  Heard of a couple of scares recently, but no confirmations.  What was thought to be Vancomycin resistant did respond, but only after lengthy treatment.  If anyone has ever read the book The Coming Plague, it'll give you a good scare, but a fascinating book.
« Last Edit: 28/10/2003 04:47:37 by bezoar »
 

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Offline nilmot

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Re: Question of the Week - Old Version
« Reply #65 on: 01/11/2003 16:51:02 »
Change their antigens?

Have caspules so they're hard to engulf?

Just some guesses....

Tom
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Offline Donnah

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Re: Question of the Week - Old Version
« Reply #66 on: 02/11/2003 00:59:13 »
I'm guessing that if we don't finish the course of any antibiotics we take, or if the course is not effective in killing the bacteria then the bacteria learn to recognize the antibiotics (as Ron said) and it's like the bacteria have been vaccinated against the antibiotics.
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Offline cuso4

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Re: Question of the Week - Old Version
« Reply #67 on: 03/11/2003 08:31:38 »
Each generation of bacteria produces quite fast, so there are always some bacteria survive under the presence of antibiotic. These bacteria then reproduce and create the next generation. This will eventually lead to a mutation in the genes of bateria.

Angel
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Offline MarkH10178

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Re: Question of the Week - Old Version
« Reply #68 on: 05/11/2003 07:02:14 »
I was just looking into this one. Those little bacteria are so damn smart - but I forget exactly how they do it. Transposons, something like that. They actually develop the ability to degrade the antibiotic that was meant to knock them off, by producing an enzyme that breaks it up. "Penicillinases" - something like that.

May I suggest a famous question? A while back somebody ran around the Harvard graduation ceremony with a videocam asking these supposedly smartest of all smart kids the question: "Why are there seasons?" - they had the worst time trying to get it right!
 

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Offline Qing

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Re: Question of the Week - Old Version
« Reply #69 on: 07/11/2003 09:50:48 »
Is the resistance temporary or permanent?Would you feel that if you start using the same antibiotics after quiting for a long time,it becomes effective again? Does that mean the bacteria are not resistant to the antibiotics any more?

Qing
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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #70 on: 09/11/2003 22:01:23 »
ANSWER TO THIS WEEK'S "QUESTION OF THE WEEK"

HOW DO BACTERIA BECOME RESISTANT TO ANTIBIOTICS ?

You've all pretty much got the answer right. The mechanism of bacterial anti-microbial resistance comes down to them making a fortuitous mistake when they are copying their DNA.

Because bacteria grow so rapidly they need to copy their DNA rapidly. Occasionally this leads to an error creeping into the genetic code. Most of the time bugs which inherit these errors are at a growth disadvantage because all of the other bugs grow much better than them and hence they are out-competed and disappear.

But if the genetic mistake changes a bacterial protein so that an antibiotic can no long bind on to it, or another enzyme made by the bacterium gains the ability to chew up antibiotics molecules (as well as doing what it did before), now the mutant bacterium has a significant growth advantage whenever that antibiotic is around. All the non-resistant bugs are killed, leaving the resistant bacterium to father a new population of resistant mutants. With all of the competing bugs gone the new mutants enjoy life without any competition - rather like the shrimp fishing in forrest gump !

So the long and the short of it is, the more antibiotics you use, the more resistance you will see. It is a fortuituous mistake on the part of the bacteria. It comes down to the principles of Darwinian natural selection.

TNS

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #71 on: 09/11/2003 22:02:35 »
We liked MarkH's suggestion, so this week's question is :

WHY ARE THERE SEASONS ?

Happy debating,

TNS

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Offline cuso4

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Re: Question of the Week - Old Version
« Reply #72 on: 10/11/2003 13:40:59 »
The Earth spins on its vertical axis at an angle (I forgot the exact value). As a result, different part of the planet receive different amount(strength) of sunlight creating seasons. This really needs a good diagram to explain properly.

In the summer of a location, the place is slightly closer to the sun and so receive slightly stronger sunlight. In the winter, the place is slightly away from the sunlight so receive slightly weaker sunlight. This also explains why places near the poles have longer daylight in the summer than those near the equator.

As to the changes in the way plants and animals behave also depend on seasons . For example, the hibernation in bears (don't know whether this apply to other hibernating animals or not) is triggered by the change in length of daylight. And people seem to be happier in summer is because seratonine is only produce in sunlight (providing you're not taking anything). This is the substance that stimulates the productiion of noradrenaline.

Angel

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Offline george

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Re: Question of the Week - Old Version
« Reply #73 on: 10/11/2003 18:45:54 »
I take on board what you've said Angel, about the planet being at an angle as it spins, but what makes the seasons change then ? How does the earth alter its degree of tilt; first it tilts one way, closer to the sun for one hemisphere, then the other. How does that happen ?
 

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Offline UScaV

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Re: Question of the Week - Old Version
« Reply #74 on: 11/11/2003 00:10:08 »
The earth is always tilted at the same angle, which is 23.5 degrees.  The tilt of the earth is always the same and doesn't change.  So as the earth rotates around the sun, the angle changes depending on where the earth is.  That's why it happens at the same time of year each year.  There are 2 equinoxs and 2 solstices a year, and on the winter solstice, the Northern hemisphere is tilted as far away as it possibly can be, and during the summer as close as it possible can be.  Also, twice a year, the the angle to the sun of both hemispheres is the same, and the amount of light and length of day are pretty much equal all over the earth(equinox).

And I don't think winter and summer have to do with the amount of time light is hitting the earth, but rather the distance is has to travel, either fighting it's way through a longer distance and more atmosphere, or a shorter distance and a smaller amount of atmosphere.

« Last Edit: 11/11/2003 00:20:45 by UScaV »
 

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Offline cuso4

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Re: Question of the Week - Old Version
« Reply #75 on: 11/11/2003 08:54:23 »
George, I think UScaV answered your question. Well explained UScaV.

"Anyone who has never made a mistake has never tried anything new." -Albert Einstein
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Offline george

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Re: Question of the Week - Old Version
« Reply #76 on: 11/11/2003 14:02:13 »
Oh right. I think I've got it now. Thanks for explaining that so clearly !

George
 

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Offline UScaV

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Re: Question of the Week - Old Version
« Reply #77 on: 12/11/2003 04:20:14 »
I wasn't sure about that last little bit.  Is that one right, where it just has to go through more atmosphere and space?
 

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Offline tweener

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Re: Question of the Week - Old Version
« Reply #78 on: 12/11/2003 04:40:36 »
Actually, the distance from the earth to Sun is so close to constant year round, that it has nothing to do with temperature.  The difference in seasons is because of the tilt making the light strike at a greater angle (during winter).  This means that for a sunbeam of a given area, there is more surface area for it to cover (and thus less light energy per unit area). The atmosphere is so thin as to make little difference in terms of distance traveled.  

As an example of this, get a flashlight with a narrow beam, shine it straight down.  Then from the same height shine it at an angle (the greater the angle the more pronounced the effect).  You can see that it appears brighter in the straight down configuration and that the beam is covering a smaller area.


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Offline Quantumcat

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Re: Question of the Week - Old Version
« Reply #79 on: 15/11/2003 08:39:34 »
Also, the part of the earth tilted toward the sun is closer, so the heat has dissapitated less by the time it gets there and it's warmer. There's longer days in summer because the part of the earth you're on gets a wider light spread (if you've ever seen a Geochrome [is that what they're called? I can't remember] then you'll know what I mean.)

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #80 on: 17/11/2003 17:57:07 »
Quantum - if you do want to discuss things related to QOTW then please feel free to start a new thread in a relevant section of the forum.

TNS

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #81 on: 17/11/2003 18:06:01 »
I think the issue of why we have seasons has been explained better than we could have done, so no further comment from us needed...

Anyway here is this week's QOTW (Question of the Week) :

"WHAT HAPPENS IF YOU LIGHT A MATCH INSIDE A SPACESHIP WHILST IT IS IN SPACE ?"

Have a go, below. Please remember that we love questions to come from you guys, so please put forward suggestions for future questions via this email address : qotw@thenakedscientists.com

TNS
« Last Edit: 17/11/2003 18:07:18 by NakedScientist »

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Offline Ians Daddy

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Re: Question of the Week - Old Version
« Reply #82 on: 17/11/2003 19:01:16 »
KABOOM!!!
 

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Offline Quantumcat

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Re: Question of the Week - Old Version
« Reply #83 on: 18/11/2003 08:02:45 »
I remember learning about flames in low gravity, I can't remember completely. It looks like a demi sphere, and it's a different colour.

I have a theory of how flames work, but no one has ever told me the real way they work. Perhaps you guys can tell me. My theory is that the heat gives the atoms energy to leap off the wood, they emit light as they go then fall back to earth as ash. Different atoms jump different heights, atoms that emit blue light don't jump as high as atoms that emit yellow light (carbon right?) but they jump higher than green light-emitting atoms. Sparks are lumps of atoms who couldn't prise themselves apart but emit light all together all the same. Because they're larger they get to jump higher than other atoms of the same kind that aren't sparks, because the breeze catches them. Coals glow because the heat has constricted them, they are too big to be carried up by the breeze and the atoms can't jump off them, so the atoms just emit their light without moving. There is considerably less matter when the fire is done because a lot of it was changed by a chemical equation into heat (I learned that at school, didn't make it up lol) the ash is all the light-emitting atoms and the chunks of black stuff were the coals. If anyone knows how it really works I would like to know. Thanks.

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Offline tweener

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Re: Question of the Week - Old Version
« Reply #84 on: 18/11/2003 15:30:12 »
Ronnie might be right if the spacecraft has pure oxygen for an atmosphere, but I think after Apollo 1 most people know better.

I believe that the flame would make a sphere (or close to it) around the head of the match.  It would keep increasing in radius while it burned, but it would not burn long.

This behavior is due to the lack of gravity causing there to be no density gradient in the air.  In a gravity field, the air is always more dense the lower you go.  When it is heated, or a hot gas is introduced, the hot gas is less dense than the surrounding air, and thus floats upward.  If there is no density gradient, then it does not float, it just stays put.  In the case of the match, the chemical reaction of burning is releasing hot gases from the wood, and thus the "flame" is going to keep increasing until the match burns out.  The match would stop burning quickly because there is no fresh air (oxygen) reaching it (it is surrounded by its own gases).


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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #85 on: 26/11/2003 11:05:43 »
ANSWER TO LAST WEEK'S QUESTION OF THE WEEK "What happens if you light a match inside a spacecraft orbiting the earth ?"

This question concerned the early pioneers of space travel a great deal. But tests showed that flames just don't work in space - to understand why not you have to first consider what a flame actually comprises.

Flames always point upwards. That's because gravity creates a density gradient in the air so that hot air, which is less dense, rises whilst cold air sinks. This is why a hot-air balloon can float.

So when something burns the hot vapourised fuel (which is rising) pulls in cold fresh air from the bottom (containing oxygen) which oxidises the fuel and creates more flame and heat. The heated vapours rise and so the process continues.

But in space, under 'weightless' conditions, there is no density gradient in the air because there is no up or down ! This means that when you try to burn something, the vapours cannot rise away and so the fire suffocates itself because fresh air (oxygen) cannot gain access to the fuel sufficiently quickly.

So, unlike Ian's Daddy's suggestion "kaboom", the more likely outcome would be something like "phutt".

TNS

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #86 on: 26/11/2003 11:08:02 »
HERE IS THIS WEEK'S Q-O-T-W :

"WHY DOES HELIUM MAKE YOUR VOICE SOUND FUNNY ?"

Have a go, below :

TNS

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Offline cuso4

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Re: Question of the Week - Old Version
« Reply #87 on: 26/11/2003 14:02:06 »
This is a guess.

We make sound by making the air vibrate. Since helium is much lighter than air so when we speak, same amount of energy will make helium gas vibrate much more. Higher frequency of sound is produced and so the voice sounds funny.

"Anyone who has never made a mistake has never tried anything new." -Albert Einstein
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Offline Quantumcat

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Re: Question of the Week - Old Version
« Reply #88 on: 26/11/2003 16:25:36 »
That's exactly what I would have said, hopefully we are right

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Offline nilmot

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Re: Question of the Week - Old Version
« Reply #89 on: 27/11/2003 12:38:46 »
Mmm... interesting suggestion.

So If I inhale lighter air e.g. Hydrogen, would that make my voice go funny as well?

Tom
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Offline chris

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Re: Question of the Week - Old Version
« Reply #90 on: 27/11/2003 16:19:52 »
If you're going to do the experiment, I wouldn;t smoke afterwards !

"I never forget a face, but in your case I'll make an exception"
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I never forget a face, but in your case I'll make an exception - Groucho Marx

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Offline nilmot

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Re: Question of the Week - Old Version
« Reply #91 on: 28/11/2003 08:31:49 »
KABOOM!!!! [:D]

P.S I don't smoke anyway Chris.. [:)]

Tom
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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #92 on: 04/12/2003 14:48:34 »
Here is the answer to last week's QOTW - "WHY DOES HELIUM MAKE YOUR VOICE GO FUNNY ?"

Most of you are on the right lines :

If you imagine your throat as a bit like an organ pipe, when the organist plays a note, one cycle of a wave, with a wavelength approximately the length of the tube, is generated inside the pipe. So when you talk you produce sound waves with wavelengths determined by the length of your throat.

The speed of a wave (c) is given by multiplying the wavelength and the frequency together (c=l.f) and this can be re-arranged to find the frequency of the sound wave (in other words how high it sounds) (f), thus : "frequency = speed divided by wavelength" or f=c/l.

But helium is less dense than the other consitutents of air and so sound travels much more quickly in helium (900 metres per second) than in air (350 metres per second). Substitute these numbers into the forumla we got above (f=c/l) and you get a value for f (helium) 2.5 times greater than f (air). As a result you voice sounds 2.5 times higher when you breathe helium.

Conversely, if you were to breathe a denser gas than air you could make your voice sound much lower.

Divers breathing a helium-rich mix (to overcome the problem of increased gas density at extreme depths) talk to their support crew using a "helium voice unscrambler" which reinforces the lower notes in their voices whilst suppressing the higher tones so that they can be understood.

TNS

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #93 on: 04/12/2003 14:51:51 »
This week's QOTW was submitted by Tom :

"WHEN WE SAY ARSENIC / MERCURY / CYANID ARE POISONOUS, WHY ARE THEY POISONOUS ? "

Over to you !

TNS

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Offline Donnah

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Re: Question of the Week - Old Version
« Reply #94 on: 04/12/2003 19:06:02 »
For mercury:

-vaporizes slightly at room temperature
-vapor is odorless/colorless/extremely toxic
-cumulative poison
-crosses blood/brain barrier
-accumulates in brain's pain centre and central nervous system
-prevents normal entry of nutrients into cells
-prevents removal of wastes from cells
-binds to immune cells and impairs function

I'd like to see the biology and chemistry wizards give a more technical view.

Now for my own rant.

Mercury
-is sometimes a component in innoculations (thermisol)
-trivalent innoculations (DPT, MMR) sometimes cause autism
-normally comprises more that 50% of amalgam (silver) dental fillings
-duh!!!!
« Last Edit: 06/12/2003 22:04:08 by Donnah »
"Remember, if you ever need a helping hand, you will find one at the end of each of your arms." - Audrey Hepburn

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Offline cuso4

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Re: Question of the Week - Old Version
« Reply #95 on: 05/12/2003 13:46:38 »
Yay, just glad that me and quantum got the helium question correct. Right here goes my answer:

The three substances work similarly. They all affect the electron transport chain (also called oxidative phosphorylation) of cellular respiration. If a cell cannot make ATP, the cell will die.

Arsenic, mercury and cyanide all can inhibit mitichondrial enzyme so that the normal substrate cannot bind. A vital reaction in the process will stop and disrupt the respiration. In the case of cyanide, it inhibits the enzyme cytochrome oxidase.

Furthermore, cyanide and carbon monoxide are respiratory inhibitors which can bind permenantly to haemoglobin preventing it bind with oxygen. This explains why a poinsoned person get breathless. If exposed to large dose, the person can soffocate and die.

Angel

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Angel

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Offline nilmot

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Re: Question of the Week - Old Version
« Reply #96 on: 06/12/2003 09:44:21 »
Ooh, we are getting some pretty good answers here.

And also thanks TNS, for putting my question on the forum.[:)]

Tom
« Last Edit: 06/12/2003 09:45:09 by nilmot »
Tom

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Offline NakedScientist

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Re: Question of the Week - Old Version
« Reply #97 on: 05/01/2004 11:56:17 »
HAPPY NEW YEAR EVERYBODY.

HERE'S THE FIRST QOTW FOR 2004, SENT IN BY PAUL SANDKUIJL.

"When you are woken up by a sound and that exact same sound was part
of your dreams ie. the alarm clock, did you begin dreaming your dream
as a result of the sound or were you already dreaming and that sound
became part of your dream?"

DOES ANYONE ELSE EXPERIENCE THIS, AND IF SO, WHY ?

TNS

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Offline bezoar

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Re: Question of the Week - Old Version
« Reply #98 on: 05/01/2004 15:12:33 »
Yes, I've had it too, and I always thought the noise triggered the dream.  What was stranger is that when my girls were babies, I always woke up before they did at night, and I would lie still and try to go back to sleep, and invariably they woke up too.  I was never sure if I awakened because I knew they were about to, or if they awakened because they sensed I was awake.

Bezoar
 

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Offline tweener

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Re: Question of the Week - Old Version
« Reply #99 on: 05/01/2004 20:20:55 »
I incorporate external sounds into my dreams all the time.  I think the sound is incorporated, but sometimes it seems the other way around.  Once a dream took it to an extreme:  The alarm was beeping, and I turned it off.  But it wouldn't quit beeping, so I banged the clock on the nightstand.  Then I unplugged it, and it still kept beeping.  Then I removed the cover and started tearing components from the board, and it still kept beeping.  Finally, I had it stripped down to a single little "box" that was beeping, with no apparent power source.  I was really tired by the time I finally came awake.

Nancy,
Babies are very sensitive to their parent's breathing and emotional status, even when they are asleep, so I think they probably woke up because you were awake.  Also, you may have awakened because they changed their breathing pattern before waking, so it may have been a "feedback" scenario.  It is amazing how aware we are even when asleep.


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John
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John - The Eternal Pessimist.