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Physics, Astronomy & Cosmology / If the Universe is expanding, what's happening to entropy?

« on: 21/04/2017 10:47:18 »

I have got really confused by the definition of the laws of thermodynamics and how they are represented.

0. Heat flows from a difference in temp.
1. Energy cannot be created or destroyed
2. Entropy always goes up
3. at t=0 entropy equals 0

This basically says to me...

1.  higher t = higher entropy
2. t is always going up
3. So everything that ever happens is irreversible and will eventually turn the universe into a giant oven.

BUT..

The universe is expanding, meaning volume change, meaning temperature drop, so entropy is decreasing.. OR is the rate of the universe expanding maintaining a constant level of entropy in the system?

I don't get it. someone must be wrong and although it is probably me, I cant spot the logic holes.

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Chemistry / Re: Why doesn't water burn?

« on: 07/12/2016 14:50:02 »

Thanks

Never really thought too hard about it really, just blindly accepted what I was told.. (bad scientific practice!)

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That CAN'T be true! / Re: What is a jet fuel surrogate?

« on: 07/12/2016 14:48:48 »

I only looked at one slide show... looked like it was put together by a 12 year old...

Sorry to be disperging guys.. but if i was shown that in any conference I went to I would laugh and walk out. I mean the sun even has a smiley face on it...

That sort of thing should be left for the attendees to doodle in on their handouts!

4

Physics, Astronomy & Cosmology / Re: Is global warming the fault overpopulation rather than motor vehicles?

« on: 07/12/2016 14:43:06 »

To reiterate my long labored point.. Global warming does not exist.. Climate Change is the correct term. (since more and more evidence is showing that it will be an ice age that we may be triggering, it is very pertinent to stress this)

The question tries to separate two linked factors, over population and motor cars.. these are undeniably linked. The more motor cars you have the higher the density of population can exist, the higher the density of population the larger the number of motor cars. So splitting these factors is impossible.

And then you enter the argument of where the climate change is man made or not, lets take the PC and general belief that it is caused by human activity.

Motor cars are only part of what contribute to the environmental impact from humans, electricity, clothing, house building, steel works and all industry in one way or another (yes including farming, some think ESPECIALLY farming) all of which develop due to increasing population and allow further increases to population (such as pharma).. 

So basically yes, overpopulation rather than motor vehicles alone, is a good answer to your question.

(I still remember in university stressing to my lecturer that using the environment as a dumping ground for all heat and waste gasses was unsustainable and would have impacts, the small minded professor said that there was nothing we could do to such a huge mass that would impact it in any significant way...)


Trees and Flora do not breath carbon dioxide... they breathe oxygen like the rest of us.. they photosynthesize with carbon dioxide top make their energy so using CO2 and they respirate? Respire? breathe.. oxygen and emit carbon dioxide.

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Chemistry / Re: Why doesn't water burn?

« on: 06/12/2016 14:03:33 »

Sorry, I work at sea, and there is a chance that if our boilers are leaking and emitting too much water vapour through the stack that we have fires caused by this water, which we call hydrogen fires. which as you point out is NOT the same as hydrogen flame.

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That CAN'T be true! / Re: What is a jet fuel surrogate?

« on: 06/12/2016 10:49:13 »

Could you volunteer for a close range inspection of chemtrails please? this information is vital to the scientific community.. We can all do long range observations by just looking up.. I feel you have much to offer in this area of scientific investigations.

Cloud seeding is a process, but you suggest that this is done to forward some hidden agenda, whereas I do not believe it is actually common place anywhere since the effects would need to be studied on a long term to see the impacts, not done on a whim by clandestine organisations.

Climate change IS visible to the naked eye, by observing the change of the ice caps, growth of trees and habitation of species to name a few.

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Just Chat! / Re: Dealing with stress and hate!!!!

« on: 05/12/2016 10:35:58 »

what if, like the majority of the scientific community, we don't?

Back to being stressed and hated I suppose

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Famous Scientists, Doctors and Inventors / Re: Scientist with no education!!

« on: 05/12/2016 10:34:52 »

Surely the plan in that circumstance is put OTHER people in harms way and record the effect on them...

I have an interesting idea about bullet proof vests... volunteers?

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Chemistry / Re: Will the release of a gas from a chemical reaction stop at a certain pressure?

« on: 05/12/2016 10:21:30 »

all them names hehe.. and yes you are right cheers chiral

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Chemistry / Re: Does cocoa powder fortify the walls of a bubble? Why are bubbles coated in cocoa able to be pic

« on: 05/12/2016 10:20:01 »

Pretty much spot on..

The cocoa powder obviously has an impact on the surface tension of the milk making these bubbles tough to break.

If you sprinkle some on top of a cappucino, if you notice the foam drops more rapidly where you havent sprinkled it..

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Chemistry / Re: Why doesn't water burn?

« on: 05/12/2016 10:15:17 »

yeah its a pain in the proverbial.

Incinerators make sure what ash you have is truly incombustible.. (solid oxides etc)

Hydrogen fires, are the only way to burn water, by splitting the hydrogen and oxygen and then burning the hydrogen again.. which yeah is splitting hairs.

Its all chemical reactions when it comes down to it anyway, I am sure you could burn stuff in all the reactive gases if you tried hard enough.

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Chemistry / Re: Will the release of a gas from a chemical reaction stop at a certain pressure?

« on: 01/12/2016 16:26:05 »

simple reaction engineering

yes it will stop.. when the gas pressure stops the reaction generating the gas.

L'hopital (name roughly) discusses the driving forces on the rate of reactions I believe or at least the effect on the equilibria

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Chemistry / Re: Why doesn't water burn?

« on: 01/12/2016 16:23:19 »

It actually does given the right circumstances see hydrogen fires.

And ash does burn in the right circumstances (see incinerator)

it all comes down to the fact that burning or combustion is the act of reacting with oxygen and only things that can react with oxygen will burn..

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Chemistry / Re: How to extract resin from a plastic bag?

« on: 01/12/2016 16:19:29 »

You will probably find that the resin itself will have a high proportion of plastic bag already melted into it.. best bet.. bake it into cookies

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Chemistry / Re: What can cause carbonated orange drink to turn colourless?

« on: 01/12/2016 16:17:48 »

drop out of the particles holding the orange colour..
If you shake it, it will mix back in

Bleaching from the sun light (not 100% sure the mechanics of this and its usually over a longer period)
Do not know how to reverse this

Chemical reaction
What is making the orange colour? could it be reacting in the acidic environment?

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Chemistry / Re: Does acid become less acidic over time?

« on: 01/12/2016 15:57:39 »

When you are etching something, what is happening is that the acid is dissolving away the part that you are etching.  But acid, like any other dissolving agent, has a saturation point. It can dissolve so much and no more.  It's like when you dissolve salt in water.  You add salt, stir, and the salt dissolves. As you keep adding salt, the longer it will take for it to dissolve.  At a certain point, the added salt will not dissolve no longer how long you stir. The water has reached its saturation point.

Sorry, this is not quite right..

The Acid is not dissolving anything

What is happening, is that the Acid is reacting with with the glass that is not coated with your resist. Producing silicon fluoride(g) and water(l). Therefore as you use it, the concentration of the acid will decrease fairly rapidly. Nothing to do with saturation, all to do with concentration.

Change out your acid regularly I say. Time the fresh runs and change out when it takes more than twice or three times this time to get the results you want. 


EDIT:

Oh and if you do get some on your skin, see a doctor.. it doesnt necessarily burn you, but it will hunt down the calcium in your bones and it LOVES that!..

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That CAN'T be true! / Re: Could a person write two different exam answers, one with each hand?

« on: 01/11/2016 10:31:18 »

Wouldn't work for me, I often write down something that I am talking of rather than what I am thinking of writing.

Think you are doing a long set of numbers on a calculator, and writing down each result. You can do this whilst holding a conversation with someone else, but if they started saying random numbers you would struggle to write down what you were going to write down over the numbers that they say.

So whilst it is possible to do 2 jobs a a time, say holding a conversation and writing a report, I doubt it is possible to manipulate each hand independently on different thought process. Manipulating your hands to do one thing and your mouth to do another is a recognized ability of most people.. we can walk and chew gum at the same time.

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New Theories / Re: Can potential energy be increased without supplying energy?

« on: 01/11/2016 10:07:03 »

Okay... to answer the question can potential energy be increased without supplying energy.. yes.. by lowering the reference energy point.

DONE.

If you measure gravitational potential energy to sea level, (gh) then measure it to a point to below sea level (gh+h) and you have increased the potential energy without supplying energy.

Other than that.. no. (although the odd behaviour of capilliary action does seem to do that)

19

New Theories / Re: Proof

« on: 28/10/2016 11:23:48 »

I like the way the box thinks, I think the same, but disagree on this point of free space.

The reason I do not think free space is a void is because I believe that space without substance would not be able to carry any force/energy. It is not unusual to consider that something that does carry force as being of substance and although describing something as the 'undetectable' is about as helpful as a chocolate kettle, it remains the best guess at what could be there..

That something we call space could be comprised of the smallest unit of existence, not holding mass or energy (hence undetectable) but concentrations thereof making up mass and allowing energy to be carried, is actually a fairly workable theory if utterly unprovable, but as we know the unprovable can also be used as the undeniable. God Theory.

IF the ether exists, it would be inconsequential to all theories and laws (no mass, no energy)
If the ether doesn't exist, it would be inconsequential to all theories and laws as well..

think like pixels on your screen, the picture exists because of them, but they do not impact the picture.

Therefore I do not see much point in either trying to prove it, or disprove it. The same as there is no point trying to tell those that believe in God that it doesn't exist.

 

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General Science / Re: How can science be correct if theories are always changing?

« on: 28/10/2016 11:01:07 »

Most science is correct and has been for decades. That's why we can discuss this topic here, and the lights stay on, and aircraft don't fall out of the sky very often. It works.

There are things we don't know yet, and we're working on it, so science is doing what it does and working to find out the solution. We'll get there.

I completely disagree, science works, but that doesn't mean it is correct. Since right and wrong remain subjective and will until we understand everything. We work on best guesses with the available information.

This is one reason I believe current scientific Laws, may accurately describe an interaction or system, but the understanding and caveats thereof are sometimes too easily dismissed. If these were not questioned we would never expand our scientific knowledge. Years ago, we did not know that light was energy, or that energy and mass were interlinked.. So laws of science had to be amended or re specified taking into account interactions and systems that were unknown of prior to these new discoveries. Think gravity for a very good example.