BF2S Forums Science questions ?

tehmoogles wrote:

Within a few seconds the Earth would reach Absolute Zero and we would all die. 8 minutes later all would be dark.

So you're saying heat travels faster than light??? Heat is just infra-red, it travels the same speed as light

Last edited by Vub (2006-07-17 05:58:27)

Vub wrote:

tehmoogles wrote:

Within a few seconds the Earth would reach Absolute Zero and we would all die. 8 minutes later all would be dark.

So you're saying heat travels faster than light??? Heat is just infra-red, it travels the same speed as light

What he said! ^^^

Heat is just another form of electromagnetic radiation such as light. The lights would go out at the same time as someone turned off the heat!

MaximaRX wrote:

DoctorFruitloop wrote:

Vub wrote:

So you're saying heat travels faster than light??? Heat is just infra-red, it travels the same speed as light

What he said! ^^^

Heat is just another form of electromagnetic radiation such as light. The lights would go out at the same time as someone turned off the heat!

The problem is that the earths atmosphere would hold heat for several days, as stated in a previous post. Yes, the earth would lose it's heat source, but there would still be radiant heat held within the atmosphere for a bit.

I never said it would be instant freeze, that's someone else, just that the source of heat and light would be removed at the same time.

You know, it is actually a myth that a black hole sucks in everything, things do actually get ejected out of the black hole called anti-matter. Supposedly everytime a particle is "sucked" in, its equivalent anti-particle is ejected. On the matter of anti-matter, I heard from somewhere that at the beginning of the universe (the big bang if you will) there was a huge war between matter and anti-matter and matter won. I don't know how true that is, I just find it odd that since they should be created in equal amounts, one can actually "win". Don't quote me on this though.

The earth would spin away first, no gravity, changes would be that it collided into another planet or star, second question, to hard, lol

earth might orbit with jupiter

Gravity by classical physics is the force of attraction which exists between any two masses.

However, Einstein's Special Theory of Relativity and his ideas point to gravity being a warping of the space-time continuum, and planets orbit stars because the fabric of space around the star is warped.

Supposedly there also was more matter than antimatter created in the Big Bang.

Vub wrote:

By Einstein's law of relativity and the idea of space-time continuum, when the sun disappears we'll remain in orbit for about 8 minutes or so because time travels at the speed of light. Therefore at the end of 8 minutes there'll be no more light, and we'll continue in a straight line out into space.

This is only true however if the gravitational field is built up at the speed of light. If the field is built up instantaneously, then immediately, before light from the sun disappears, we'll start travelling in a tangent into space. Think about it, if a star a billion lightyears away goes supernova, its light will continue shining down to Earth for a billion years, however in that billion years it will actually not exist anymore. So is it possible that its gravitational hold on the Earth will also exist for a billion years even if it's no longer there?

edit: added "of attraction" to gravity definition.

Last edited by Vub (2006-07-17 06:43:18)

elmo1337 wrote:

Fz = g × m

in the netherlands g is a constant, 9,81 m/s, m is mass of the object in kilograms

That's the force associated with a falling body.

Gravity is an attractive force between two bodies expressed by the product of their masses invertly proportional to the distance between them squared.

Last edited by DoctorFruitloop (2006-07-17 06:44:13)

elmo1337 wrote:

SargeV1.4 wrote:

What is gravity? (No dictionary or smartass answers please)

Zwaartekracht in het nederlands

Fz = g × m

in the netherlands g is a constant, 9,81 m/s, m is mass of the object in kilograms

ok, here's an example:

What is a TV?

With a TV you can watch films and shows, or play games.

NEIN

The answer I would be looking for is:

It's a square box, in which *technique to get light on screen explained*


So for gravity I'm looking for the same answer

what is it?

Vub wrote:

Gravity by classical physics is the force of attraction which exists between any two masses.

However, Einstein's Special Theory of Relativity and his ideas point to gravity being a warping of the space-time continuum, and planets orbit stars because the fabric of space around the star is warped.

I've now wasted about half a day thinking about this as it's much more interesting that what I should be doing.

How fast would everything die without the sun?

I figure that the atmosphere would hold enough heat to keep things alive for probably a few days at the most before temperatures dropped to 50-100 below zero which should kill off anything exposed to the air. That's pretty much all birds, mammals and reptiles. Insects are small so they should be terrible at retaining body temperature, so they will probably begin to die off first. Many species of insects can survive being frozen and thawed out, but without an external heat source they're doomed to stay frozen. Anything cold blooded obviously will go down before us warm blooded mammals. 

Plants, I'm not too sure about their exact fate time line. Obviously without light they can't make glucose, but will that run out before the temperature drops enough to freeze the water in them? I feel they'll freeze first as they don't have much in the way of metabolism to warm them up.


What about us? To survive the longest I think going underground is a sensible option, the further the better (the air will cool much faster than the ground) The key concerns for us are oxygen, heat, water, food.

Oxygen - I can see 3 options, live off any temporary supply of oxygen cylinders / liquid oxygen you can find in time and assume other things will kill you off faster.
              Try to create a way to ventilate air from the surface and hope you have the energy means to heat it up to a reasonable temperature. You'll need to set this up in a matter of a day or so, so probably too complex.
              Grab a load of plants and hope they can make enough oxygen to keep you going. A reasonable idea, especially if combined with the first option, they would require your heat, water and nutrients though.   

Heat - most public power/gas requires above ground facilities which won't be running so that's not an option.
          Fire would require both a lot of fuel and makes poisonous gases that would need venting.
          A petrol generator allows you to have the exhaust gasses away from the heat source and provide light, but the petrol supply would be finite.
          If you're lucky enough to live near some volcanically active area you could try moving in down there. the heat is supplied by the earths core, so it will last much longer than you will. Poisonous volcanic gasses may be problematic but this could be your best option. Also you'll have no light source at all, so get used to being essentially blind.

Water - All surface water will be ice very quickly, so no rainwater will be seeping down. Any supplies or water taken down with you will eventually run out. If you chose a good cave system it is quite likely to contain a decent amount of water in the form of underground lakes. Provided it's drinkable, there are relatively few of you and you have the energy source required to melt it if it does freeze you could be alright.

Food - If you're lucky enough to have solved the previous three problems then food could be an issue. As far as surviving against extreme cold goes, it's survival of the fattest. You'll probably want to spend the first couple of days eating as much fatty food as possible to bulk up. After you've said goodbye to the surface you'll probably need to have all the food you'll ever need down there with you, so I hope you like spam and beans because long life tinned foods are way forward here.

Unless some government has facilities where all these problems sorted, the chances of getting everything ready before the surface became uninhabitable is almost nil. Assuming my cooling rate prediction is reasonable then even the most hardy humans will most likely be dead within a week or two. The last human survivors will probably die in a nuclear missile bunker somewhere.


What about sea life?
The ocean will cool much slower than the air or ground as water has a large heat capacity. The deep oceans will therefore probably take many months or even years to actually freeze solid, aided by salt content and high pressure, both of which lower the waters freezing point. life in the deep ocean doesn't rely on sunlight, so that isn't a problem, it does however require organic matter falling from the upper ocean (dead stuff) to eat to survive. As the oceans cool there will be a large abundance of dead things falling down as things like phytoplankton that require sunlight and then Zooplankton which eat them then the rest of the food chain. This should provide enough dead matter for life down there to eat for many months, but ultimately will run out and starve the remaining life to death if the oceans don't freeze first.

Hydrothermal vents.
These are where the true survivors will be found. Geothermally heated water vents provide the energy to keep life there going. The life there doesn't need sunlight, external heat or dead organic matter, it is sustained bacteria that feed on the highly mineral enriched water that is superheated by magma pushed up from the earths core. Heated and fed by geothermal processes, life here could theoretically last millions of years.

So there you go, most of this was poorly if at all researched, so if I've said anything stupid please point it out.

Last edited by .:XDR:.PureFodder (2006-07-17 08:43:59)

Are you sure?

We will let all nukes blow up in the atmosphere to give us some more hours to play battlefield. And everyone will be nice to each other and not TK over planes and salute each others skills etc.

Then we will have have incredible luck because all the gas giants will collide and the resulting body will produce lots of heat while calming down AND miraculously Earth will be captured by this body and give us a perfect orbit. At this stage, captain Picard will decide that our situation permits an exception from the Prime Directive and will give us 5 new planets to colonize, a seat in the Federation and lots of cool new technology like phasers and stuff.

Last edited by voltage (2006-07-17 08:59:58)