Post your science questions here!

[mik]

Originally Posted by Big Damo

Why is the sky blue?

Because Collingwood lost !

[supershifty]

Why does One Direction and Justin Bieber exist? FFS - really!

[Ford_The_Win]

Originally Posted by XRDeeze

aye bro why do people go on about Evolution, yet their still apes on earth

It's because most of the primates, humans included, evolved from a common ancestor. Homo sapiens, apes and chimpanzees (our closest genetic relatives in the animal kingdom) evolved from the same animal millions of years ago. We share around 97% of our DNA with chimpanzees and about 90% with apes. Other primates like baboons, vervets and other monkeys with tails diverged much earlier but we still share over 75% of the same DNA with the cheeky devils and that is because, as I said, we all evolved from the same animal at some stage.

[2011G6E]

The sun is the wrong kind of star to make a supernova...it will expand and then shrink again. Not enough mass to "blow up"...it would need to be a much larger type of star like we see such as Betelguese.

[XR6T0Y]

Ahh ok. The centre of the Sun is dark matter. Yes?

Is this why it is able to sustain such heat?

[BHDOGS]

[QUOTE=2011G6E]It doesn't...that's why it's a spiral instead of just a big spinning disc. [QUOTE=2011G6E]

Um no they rotate at practicly the same speed

[creative]

Do you think they ran out of cool names when they named the quarks?

[Iggypoppin']

I know they ran out of cool names to name large stars. "Binary star number something something" isn't really that interesting for a star several hundred times the size of our sun.
Here's a numbers one for some people, no googling, see if you can get it. X^3 x Y^3= z^3. Solve for the unknowns, positive integers above 2 only!

[BHDOGS]

Surprised nobody's brought up the newest discovery of the Higgins particle that gives all objects mass think bout your 600hp car weighing 50kilos due to the Higgins field generator haha

[Nova 8]

Meaning of life is to procreate.

Question: What is gravity

[Nova 8]

Originally Posted by sk8xr8

why do fish suffocate when you take them out of the water?

Not all fish do, labyrinth have evolved with a lung and can breath air which allow them to live in stagnant water and they can even move over land between bodies of water. Other fish that can breath air are snake heads, mudskippers and some eels. The lung fish is another fish that does this and has the closest thing to a lung in the fish world. They can survive months out of water also on a side note an albino Australian lung fish sold for $50,000 a few years back o.O

Evolution is a grand thing, fish that need to see out of water also need to evolve a different type of eye to see in the air or so I have read.

[burnz]

Originally Posted by XR6T0Y

What's the meaning of life

thats easy..
the meaning of life is one's own perspective.

[2011G6E]

Originally Posted by XR6T0Y

Ahh ok. The centre of the Sun is dark matter. Yes?

Is this why it is able to sustain such heat?

Nope, it's a big ball of hydrogen. In the center under the staggering pressures and temperatures, hydrogen is fused into helium, releasing energy which seeps up to the surface. and is radiated out in all directions.
This is the future of the sun according to latest studies:

The future looks bright—maybe too bright. The sun is slowly expanding and brightening, and over the next few billion years it will eventually desiccate Earth, leaving it hot, brown and uninhabitable. About 7.6 billion years from now, the sun will reach its maximum size as a red giant: its surface will extend beyond Earth’s orbit today by 20 percent and will shine 3,000 times brighter. In its final stage, the sun will collapse into a white dwarf.

Although scientists agree on the sun’s future, they disagree about what will happen to Earth. Since 1924, when British mathematician James Jeans first considered Earth’s fate during the sun’s red giant phase, a bevy of scientists have reached oscillating conclusions. In some scenarios, our planet escapes vaporization; in the latest analyses, however, it does not.

The answer is not straightforward, because although the sun will expand beyond Earth’s orbit, or one astronomical unit (AU), it will lose mass along the way. As a result, Earth should drift outward as the gravitational tug lessens over time. (At its maximum radius of 1.2 AU, the sun will have lost about one third of its mass, compared with its current heft.) In this way, Earth could escape solar envelopment.

Here's another good description in laymens terms of the suns life cycle and eventual end:
http://cde.nwc.edu/SCI2108/course_do.../lifecycle.htm


One interesting thing which anyone with an interest in science should get a smile out of is the future of Earth and the way green groups seem to think the Earth is solid, unchanging, and will always be here just like it is now.
Our entire civilisation has arising during one unseasonably nice 10,000 year period of Earths history...it has normally been either much much colder or much much hotter than it is at the moment...we are living in a pleasant time which will inevitably change and swing back to one extreme or the other...most likely ice time again. The Earth isn't here for our convenience alone, it couldn't care less if we were here or not (even if it somehow "knew" we were here in the first place).
The world has no future...it will be baked in less than a billion years, and no life at all will survive beyond another billion or two. In fact all it would take right now is one massive meteorite or comet to swing in unannounced and smack us in a big way, and it would all be over.
Green groups rave on about the Barrier Reef as if it's somehow eternal and has always been there, when it has really only been there abut 14,000 years, growing on what were coastal plains after sea levels rose dramatically by a few hundred meters at that time (interestingly, the aborigines would have seen this happening over a period of only about 300 years).

Nothing on this planet is eternal, nothing will be around as we know it now in the distant future, so enjoy it as it is now, but don't fool yourself that the world is here purely for mankind.

[seedywagon]

Originally Posted by Iggypoppin'

I know they ran out of cool names to name large stars. "Binary star number something something" isn't really that interesting for a star several hundred times the size of our sun.
Here's a numbers one for some people, no googling, see if you can get it. X^3 x Y^3= z^3. Solve for the unknowns, positive integers above 2 only!

I remember seeing this problem in a first-year uni maths class and being like ???

IIRC it was undefined for any positive integers above 2?

[Ducati888]

Originally Posted by ute83

Why doesn't the sun blow up?

It is blowing up. it's a fusion reactor, contained by gravity.

[Ducati888]

Originally Posted by XR6T0Y
What's the meaning of life


Why does there have to be a meaning? It just is.

[Autolite]

What is dust?

[MAD]

In physics we know that a given mass of gas at two different volumes will have different pressures.
Why is the expansion of the universe accelerating?

[flappist]

Originally Posted by seedywagon

I remember seeing this problem in a first-year uni maths class and being like ???

IIRC it was undefined for any positive integers above 2?

Guess again.

It is a simple progression

e.g. x=8, y=16, z=128 (8*16)

8^3 = 512
16^3 = 4096
512 * 4096 = 2097152
128 ^ 3 = 2097152

9, 27 & 243

there are bazillions of correct answers

[goose1000]

Originally Posted by jaydee

If you are flogging through space in your space ship at night at light speed and turn on your headlights, will you be able to see where you're going?

If you travelling at the speed of light time for you has stopped so you wouldn't be able to turn on your lights in the first place. Then there is the whole matter that your mass increases with your speed so if you are travelling at the speed of light you would also have an infinite (read impossible) mass, hence photons have no mass.

And yes I am a nerd!

[goose1000]

Originally Posted by MAD

Why is the expansion of the universe accelerating?

I thought this was an answer science questions thread not win a nobel prize for physics thread!!!!

[flappist]

Originally Posted by MAD

In physics we know that a given mass of gas at two different volumes will have different pressures.
Why is the expansion of the universe accelerating?

As we tend to observe time in only one dimension, space in three dimentions and newtonian acceleration is distance per time squared the axiom is that it the amount of space is changing and not time.

If time is, as theorised, at least three dimensions then possibly this is an observation of the second or even second and third dimensions.

Or maybe it is just running down hill........

[MAD]

As there is no 'centre' and everything is expanding relative to each other, could it be that it's just the space between the items that is expanding, and everything that is at the edge of the universe is, always was, and always will be, at the edge of the universe.

[XRDeeze]

Originally Posted by 2011G6E

There's no rule that said we had to evolve intelligence of our level, it was an accident of evolution.

[AndrewR_AUII]

Ultra high speed photography (1,000,000,000,000 frames/second):
http://www.youtube.com/watch?v=SoHeWgLvlXI

[b0son]

Originally Posted by sk8xr8

why do fish suffocate when you take them out of the water?

the filaments that make up the gill surface need water to function (the water keeps the filaments separated which maintains a high surface area). no water, and they all collapse in a heap, massively reducing the surface area and therefore efficiency.

[Kable72]

Originally Posted by MAD

As there is no 'centre' and everything is expanding relative to each other, could it be that it's just the space between the items that is expanding, and everything that is at the edge of the universe is, always was, and always will be, at the edge of the universe.

Wouldn't that mean that everything is drifting apart?

[flappist]

Originally Posted by XRDeeze

image

Absolutely correct.

The evolution of life on earth over the last 100,000,000 years or so was an experiment by aliens who come to visit occasionally to see how we are going.

Unfortunately a couple of thousand years ago a practical joke was played which has been a source of amusement for them ever since.........

[Madaya]

Originally Posted by goose1000

I thought this was an answer science questions thread not win a nobel prize for physics thread!!!!

goose1000, these are questions that have been bandied around the barby, and no, not a barby of Physics Majors. Interesting stuff and funny as well. It's amazing what us average folk, together, can sort out i.e. if everyone contributes their bit, then the answers and questions happen.

[xisled]

What came first the chicken or the egg.

Just had to say it.