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Physiology & Medicine / Why does a hair sometimes change colour as it grows longer?

« on: 18/05/2013 21:36:49 »

Hi, i've been wondering for a while why some hairs are light at the root but get darker towards the tip? I was examining my sideburns the other day and noticed i am starting to grow thicker black hairs where before there were only blondy-brown hairs, thats fine, but what gets me is that some are light at the root. Aren't hairs dead? If they are turning black shouldn't it be stright from the root outwards?

Am i missing something?

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Physics, Astronomy & Cosmology / Re: Can time drift in relation to space?

« on: 06/09/2012 18:45:28 »

I think i'm starting to get it, thanks guys. Time flows relative to gravitational force not position in space. I don't get how velocity changes time though, but i'll google time dilation. And i wonder if any of this is linked in some roundabout way to why the graviton is a theoretical particle.

Drinks all round at my restaurant in south africa.

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Physics, Astronomy & Cosmology / Re: Can time drift in relation to space?

« on: 05/09/2012 12:32:07 »

Thanks for the reply but i'm not talking about measured units of time. I'm saying that if in one part of space, time flows faster than another part of space, does this difference stay constant or does it change?

I'm not sure if i agree with

Time "moves" depending on the progression and expansion of matter....if nothing progresses or expands, then time basically stops...

Are you talking about movement of matter or temperature? Expands how? I don't get it.

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Physics, Astronomy & Cosmology / Can time drift in relation to space?

« on: 04/09/2012 18:31:44 »

I phrased the question as best i could. I was thinking about that theoretical example; the one where you fly two clocks set at the same time on two planes flying at the same speed around the world in different directions, and when they meet up there is a slight difference in the speed of the clocks because of how time flows differently in different parts of space.

I was wondering if it is possible for the rate of time in one area of space to change it's rate of flow, or for the rate of flow of time to change position? I imagine it to drift like smoke or a cloud through space but that's just me trying to visualize. I'm not sure how we would measure it as we are continuously moving through the universe even if we appear still. And i'm not sure if my understanding of time being relative to space is correct, enlighten me.

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Physics, Astronomy & Cosmology / Re: Can Gravity Change Light?

« on: 08/05/2012 09:14:52 »

Thanks guys.

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Physics, Astronomy & Cosmology / Re: Can Gravity Change Light?

« on: 06/05/2012 09:29:16 »

To Pmb

So you saying if i were near the black hole the light would appear to travel at the usual speed of "c" because of time being relative to space, but if i were observing from a distance it would appear to travel slower?

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Physics, Astronomy & Cosmology / Re: What happens when a star falls into a black hole?

« on: 04/05/2012 13:42:58 »

I read this recently, quite cool.  http://arstechnica.com/science/news/2012/05/a-burp-of-light-from-a-black-hole-reveals-that-it-ate-a-star.ars

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Physics, Astronomy & Cosmology / Re: Can Gravity Change Light?

« on: 04/05/2012 13:02:19 »

Thanks for the reply. I'm not so good with maths.

Are you saying gravity can slow or speed up light? Does a red light move slower than a violet light?

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Physics, Astronomy & Cosmology / Can Gravity Change Light?

« on: 03/05/2012 19:41:18 »

Hi, i was just wondering something.

If light is affected by gravity like near a black hole, is it possible for gravity to slow down or speed up a wave of lights frequency? I imagine it as something like a slingshot effect where the light is close enough to be affected by a black hole but not passed the event horizon so it can escape. Would this potentially change the colour of light if it does happen?

Am i misunderstanding something?

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Chemistry / Can you mix molten metal and molten salt?

« on: 13/10/2010 11:24:41 »

Cool, thanks. They make carbon steel, so i was wondering what happens if you try it with other stuff.

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Chemistry / Can you mix molten metal and molten salt?

« on: 12/10/2010 12:57:30 »

I was wondering if it is possible to mix molten metal and molten salt. I understand the difference in boiling points might play a role, but if one were to get it right what would the properties of the product be?

Tried to find it on the internet but couldn't.

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Chemistry / Does the Sun smell?

« on: 12/10/2010 12:52:57 »

Yes actually, to the space question. In 2009 astronomers stated that the center of our galaxy actually would smell of rum. In a search for organic compounds they also found quantities of ethyl formate, which implies that our galaxy tastes like raspberries. Tastes like raspberries and smells like rum.

Well, a popular drink in Mozambiques is rum and raspberry, really tasty.

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Technology / Why is my plasma ball messing with my screen?

« on: 28/09/2010 15:14:27 »

Thanks

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Technology / Why is my plasma ball messing with my screen?

« on: 26/09/2010 12:57:53 »

Hi, i have a computer screen that is switch on by one of those new kind of switches that is activated either by the heat from your finger or the electricity or some other form of magic. It would switch on or off by itself. I was slightly puzzled by this but i narrowed it down to my plasma ball lamp that is within a meter or so of the switch.

I would like to know why this is. My screen model is the samsung syncmaster T260.

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Plant Sciences, Zoology & Evolution / Is it possible to harvest DNA from 3000 year old bones?

« on: 23/08/2010 12:58:06 »

Hi, i was reading this article about some giant turtle's on an island and how they found their 3000 year old bones. They are extinct due to human hunting. I was wondering if we are able to extract DNA from the bones? Would it be degraded? Would it be legal? Would we be able to recreate the species?

Here's the linkhttp://www.wired.com/wiredscience/2010/08/last-giant-land-turtle

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Chemistry / Can you make a mercury alloy?

« on: 17/08/2010 08:41:33 »

I was driving in the car the other day, and for some reason i thought of mercury alloys again. I was wondering, do you think it would work if you created something like a pressure cooker for metal? Where you could heat mercury but the pressure would keep the gas as a liquid, then you could heat it up with another metal with a higher melting point and when they are both liquid they can mix. Not sure how it would work when you cool it down.

I don't have any reason to want to make a mercury alloy, it just makes me wonder because of the difficulty in doing so, and what a titanium mercury alloy might look like.

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Physiology & Medicine / How does hair know when to stop growing?

« on: 16/08/2010 13:22:06 »

i've always wondered why some hairs on your body grow to a certain length and then seem to stop growing, or at least slow down. I suspect it might work the same way a dogs coat doesn't keep growing, but if you shave a patch it grows back.

How does your body register the length of your hair? Is it maybe a sensitivity to light? How does it work?

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Chemistry / Can you make a mercury alloy?

« on: 03/05/2010 15:35:23 »

Hi, i've been looking on the net for mercury alloys but all i seem to find are amalgams. Is it possible to throw mercury into another molten metal (eg. iron, titanium) and let it cool into a alloy of the two? would mercury boil into a gas before they mix? And if possible what would the characteristics of the metal likely be?

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Cells, Microbes & Viruses / Is it possible to take a telemerase suppliment?

« on: 12/03/2010 06:25:41 »

I'll get back to you on that one.

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Cells, Microbes & Viruses / Is it possible to take a telemerase suppliment?

« on: 11/03/2010 17:04:46 »

I thought that the only reason your telomeres shorten is because there isn't the telemerase present to bond with them when they split during cell replication. I thought we could just add it to our systems and it would just happen. Is this wrong?

It came to me when i heard about how some sea urchins can live indefinately (and also how there is very little reported sea urchin cancer in comparison to their telemerase activity, even though i have no idea who checks for sea urchin cancer, that job must suck)