# Thermodynamic questions,

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How much energy can a house brick absorb?

How much energy can the Earth absorb?

If by thermodynamics a magnet starts to reach its curie point and loses its magnetism force, what effect is the thermodynamics having on the molecules in the magnet?

Hot metal expands, and increases mass by adding energy/heat, what on a molecular level is happening?

Edited by Relative
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Heating an object does not increase its mass, it increases its volume. On a molecular level, the particles are vibrating faster and faster, bumping into each other more and thereby increasing their net movement away from each other.

Edited by /backslash/
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Heating an object does not increase its mass, it increases its volume. On a molecular level, the particles are vibrating faster and faster, bumping into each other more and thereby increasing their net movement away from each other.

Increases volume, you mean it expands becoming less dense but keeps its mass conserved at all times?

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Heating an object does not increase its mass, it increases its volume.

Actually, it does by a really, really tiny amount due to relativistic effects (e=mc2 and all that). In pretty much all real-world scenarios, this can be ignored.

Unfortunately, Relative has a habit of latching on to irrelevant details like this.

How much energy can a house brick absorb?

Do you mean: "how much energy can it absorb before it melts, or bursts into flames, or otherwise ceases to be a brick"?

If so, I have no idea.

If not, can you rephrase the question.

How much energy can the Earth absorb?

Ditto. What do you mean by "how much"?

If by thermodynamics a magnet starts to reach its curie point and loses its magnetism force, what effect is the thermodynamics having on the molecules in the magnet?

I think this is due to the increased motion of the atoms causing them to become unaligned so that their magnetic fields are not all pointing the same way.

Hot metal expands, and increases mass by adding energy/heat, what on a molecular level is happening?

The increased kinetic energy of the atoms means they are moving faster which stretches the bonds between them. They are therefore further apart and the material is less dense. (That is probably highly simplified.)

If you continue heating, then the bonds may break completely causing the metal to become liquid.

Increases volume, you mean it expands becoming less dense but keeps its mass conserved at all times?

In practical terms, yes.

Edited by Strange
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How much energy can the Earth absorb?

''Ditto. What do you mean by "how much"?''

The Earth emits energy?

The Earth also absorbs energy from the sun?

What amount of energy is released, compared to the energy gained?

If the energy was not released, what quantity of energy could the Earth hold before there was any significant effects?

By greater carbon in the atmosphere the atmosphere can hold more heat also by Thermodynamics?

In thermodynamics if we had two house bricks that were heated to their maximum state, loss would be equal to input?

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The Earth emits energy?

The Earth also absorbs energy from the sun?

Yes to both.

What amount of energy is released, compared to the energy gained?

It is approximately the same. If it weren't the Earth would get hotter or cooler. Currently it is absorbing slightly more energy than it loses. Hence: global warming.

If the energy was not released, what quantity of energy could the Earth hold before there was any significant effects?

Depends what you mean by "significant". It is already heating rather too much for comfort.

By greater carbon in the atmosphere the atmosphere can hold more heat also by Thermodynamics?

It is slightly more complicated than "can hold more". It is to do with how transparent the atmosphere is to infra red.

In thermodynamics if we had two house bricks that were heated to their maximum state, loss would be equal to input?

Again, "maximum state" isn't very meaningful. But if they are at a constant temperature (any constant temperature) then the input energy will equal the output.

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Yes to both.

It is approximately the same. If it weren't the Earth would get hotter or cooler. Currently it is absorbing slightly more energy than it loses. Hence: global warming.

Depends what you mean by "significant". It is already heating rather too much for comfort.

It is slightly more complicated than "can hold more". It is to do with how transparent the atmosphere is to infra red.

Again, "maximum state" isn't very meaningful. But if they are at a constant temperature (any constant temperature) then the input energy will equal the output.

I said this in another thread, but did not not word it that good- Currently it is absorbing slightly more energy than it loses. Hence: global warming.

''It is slightly more complicated than "can hold more". It is to do with how transparent the atmosphere is to infra red.''

What do you mean by this?, please explain the part in bold,

Edited by Relative
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Energy arrives from the sun in the form of visible light and ultraviolet radiation. This radiation passes through the atmosphere and warms the Earth. The Earth then radiates some of this heat as infrared radiation. Greenhouse gases in the atmosphere absorb some of this heat, then re-emit it in all directions - including back to the Earth's surface. Hence the Earth gets warmer.

More: http://www.skepticalscience.com/empirical-evidence-for-co2-enhanced-greenhouse-effect.htm

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Energy arrives from the sun in the form of visible light and ultraviolet radiation. This radiation passes through the atmosphere and warms the Earth. The Earth then radiates some of this heat as infrared radiation. Greenhouse gases in the atmosphere absorb some of this heat, then re-emit it in all directions - including back to the Earth's surface. Hence the Earth gets warmer.

Thank you for the link, I had better not tell you what I thought and stick to topic.

Thank you for the link, I had better not tell you what I thought and stick to topic.

Ok , I have got to ask, I am in agreement with most of what you said about the link, however one point I have to mention, you say the heat of the green house gases returns some back to the earth, I have got to ask this, If heat rises, how can it return to the earth?

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Arr i see, but also , I have to ask, if the atmosphere were to be full of energy, am I correct in thinking that then the earth would not emit anything?

or as the atmosphere heats, will it slow down how much is released because the exchange rate is slowed by the atmosphere been warm with energy and a slower intake rate as such?

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if the atmosphere were to be full of energy, am I correct in thinking that then the earth would not emit anything?

or as the atmosphere heats, will it slow down how much is released because the exchange rate is slowed by the atmosphere been warm with energy and a slower intake rate as such?

I don't understand the question.

If the atmosphere is hotter then the Earth, then no heat will leave the Earth, but will flow from the atmosphere to the Earth. But at the same time the atmosphere will radiate to space faster because it is warmer. But also, the atmosphere is not all at the same temperature, and the Earth is not all at the same temperature, and the seas are not all at the same temperature. And the amount of heat in the atmosphere varies with humidity and pressure. And all these temperatures change all the time as energy flows between different parts of the system and winds blow and sea currents move and ...

That is why it is so hard to model exactly what happens.

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I don't understand the question.

If the atmosphere is hotter then the Earth, then no heat will leave the Earth, but will flow from the atmosphere to the Earth. But at the same time the atmosphere will radiate to space faster because it is warmer. But also, the atmosphere is not all at the same temperature, and the Earth is not all at the same temperature, and the seas are not all at the same temperature. And the amount of heat in the atmosphere varies with humidity and pressure. And all these temperatures change all the time as energy flows between different parts of the system and winds blow and sea currents move and ...

That is why it is so hard to model exactly what happens.

Ok so you are saying this diagram but with atmosphere to consider?

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Ok so you are saying this diagram but with atmosphere to consider?

I suppose so. But "the atmosphere" means 1,000s of variables which change in every location, altitude and moment. Plus the input from the sun varies all the time.

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I suppose so. But "the atmosphere" means 1,000s of variables which change in every location, altitude and moment. Plus the input from the sun varies all the time.

Thank you, yes I understand that the thermodynamics is a part of a random variable system.

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Thank you, yes I understand that the thermodynamics is a part of a random variable system.

Complex, rather than random.

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Complex, rather than random.

Ok, complex, but no that complex to understand what is happening.

Clouds - they act has a thermodynamic filter?

They are grey because of carbon increase and other filtered elements, where as, if there was no carbon they would be transparent like water?

Edited by Relative
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Ok, complex, but no that complex to understand what is happening.

It is easy-ish to understand at a very basic level. But it is an immensely complicated area of science. For example...

Clouds - they act has a thermodynamic filter?

Clouds do many things. They stop light reaching the Earth and reflect it back to space so they may cause cooling. They alos absorb some light so may get warmer. They reflect light and infra-red back down to Earth and so may cause warming. They change the heat capacity of the atmosphere. The amount of cloud might increase or decrease as the climate changes so they might accelerate or slow climate change. They might ... well, you get the picture.

They are grey because of carbon increase and other filtered elements, where as, if there was no carbon they would be transparent like water

First, when people talk about "carbon" in this context it is shorthand for carbon-dioxide (and other carbon-based greenhouse gases, such as methane). They don't mean the black stuff that charcoal is made of.

Second clouds are white or grey because of the scattering of light by the water droplets and ice crystals. I assume the colour depends on the size of the droplets, but I don't know for sure.

tappetty-tappety-tap ... Oh, apparently it is because they are thicker.

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All clouds are white. They're water. The carbon dioxide in the atmosphere does not change their colour.

It does change the frequency dependent permittivity of the atmosphere though. Which results in the above discussed warming.

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Relative: congratulations for asking questions and not giving in to the temptation to say the sceince must be wrong because your intuition/imagination says something different!

Keep it up.

Why do clouds turn gray before it rains?

http://www.scientificamerican.com/article/why-do-clouds-turn-gray-b/

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Relative: congratulations for asking questions and not giving in to the temptation to say the sceince must be wrong because your intuition/imagination says something different!

Keep it up.

Why do clouds turn gray before it rains?

http://www.scientificamerican.com/article/why-do-clouds-turn-gray-b/

Thank you for the link and yes I am resisting to saying what I think, although yes , in some of the information I have already received, I could make several cases for debate.

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Unless I ask questions based on the thermodynamics and let you answer it for yourselves.

In this picture it is of smoke in water, how does this compare in thermodynamics to a cloud?

With it been a cloud of smoke?

Smoke is denser than water so can absorb more heat than the water?

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In this picture it is of smoke in water, how does this compare in thermodynamics to a cloud?
With it been a cloud of smoke?

Firstly, it can't possibly be smoke in water. It might be some other liquid in water or, more likely, a very clever piece of photoshop. Although you didn't (as usual) provide a source, it comes from here:

http://missparisienne.deviantart.com/art/Smoke-under-water-349335450

This is an art website.

Also, I doubt it would have any similarity to the thermodynamics of clouds in air: water is a liquid, it has a different density than air, it has a different specific heat, and so on. Smoke (or whatever it is) has nothing in common with clouds.

You are, perhaps, being misled by a superficial visual similarity.

Smoke is denser than water so can absorb more heat than the water?

How can smoke be denser than water. Smoke floats in the air. Water doesn't.

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Firstly, it can't possibly be smoke in water. It might be some other liquid in water or, more likely, a very clever piece of photoshop. Although you didn't (as usual) provide a source, it comes from here:

http://missparisienne.deviantart.com/art/Smoke-under-water-349335450

This is an art website.

Also, I doubt it would have any similarity to the thermodynamics of clouds in air: water is a liquid, it has a different density than air, it has a different specific heat, and so on. Smoke (or whatever it is) has nothing in common with clouds.

You are, perhaps, being misled by a superficial visual similarity.

How can smoke be denser than water. Smoke floats in the air. Water doesn't.

Water is used in a bong to purify the smoke that comes out of the flute.

water does float in the air it evaporates and becomes tiny particles ?

smoke travels through water very well

sorry for the diagram it is google pic

The carbon dioxide in smoke can absorb more heat than water psi?

It is a shame you can not just suck the clouds into a huge cargo plane...........through a carbon filter

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The atmosphere is really really big and you couldn't just do the clouds.

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