Nuclear Bomb Comparisons

[Krumlink]

If you were in a chamber that WAS becoming a vacuum, wouldnt that do more damage, as in it ripping all the air out of your body (stomach, lungs, intestines)? It seems like a present vacuum and a forming vacuum can have different effects.

 

[Leftyretro]

If you were in a chamber that WAS becoming a vacuum, wouldnt that do more damage, as in it ripping all the air out of your body (stomach, lungs, intestines)? It seems like a present vacuum and a forming vacuum can have different effects.

Most likely that would just suck

Lefty

 

[Hank Fletcher]

I can't see anything popping on a human body in a vacuum, other than any part that at normal sea level would retain pressurized gas. See how my question about farts in space was relevant after all? The best I can tell that would happen is that you'd suddenly let one rip.

Also, I don't understand this whole blood, etc boiling bit. My understanding was that liquids boil under greater pressure and heat, of which there is little of either in space.

 

[Nigel Goodwin]

Also, I don't understand this whole blood, etc boiling bit. My understanding was that liquids boil under greater pressure and heat, of which there is little of either in space.

You've got it the wrong way round, liquids boil at a lower temperature if the pressure is lower - which is why you can't make a cup of tea on a high mountain, because the water boils before it's hot enough to make tea.

This is also why car cooling systems are pressurised, so the water can stay liquid even though it's above normal boiling point.

 

[audioguru]

Something that compresses gets hot when it is pressurized. Liquids cannot be compressed like air can.

Something that expands at low pressure gets cold. Liquids cannot expand at low pressure like refregerator coolant can (actually, it evaporates at low pressure).

 

[HiTech]

Well yes and no to that-- A supercharger compresses liquid fuel... that is after it's been somewhat atomized with incoming air. Same for diesel fuel. It gets compressed to the point that is super heats and requires only a glow plug instead of a spark plug.

 

[Nigel Goodwin]

Well yes and no to that-- A supercharger compresses liquid fuel... that is after it's been somewhat atomized with incoming air. Same for diesel fuel. It gets compressed to the point that is super heats and requires only a glow plug instead of a spark plug.

I thought a super charger (just like a turbo charger) simply forced air under pressure into the engine?.

 

[Leftyretro]

General rule:

Pump = pumps liquid

Compressor = compresses gas

Liquid passing through a compressor can cause damage. Liquids are uncompressable.

Gas passing through a pump causes cavitation.




Lefty

 

[Hank Fletcher]

You've got it the wrong way round, liquids boil at a lower temperature if the pressure is lower - which is why you can't make a cup of tea on a high mountain, because the water boils before it's hot enough to make tea.

This is also why car cooling systems are pressurised, so the water can stay liquid even though it's above normal boiling point.

But what's happening when I hold the lid down while I make spaghetti? Just the pot and water on the stove by itself, I can hear the water bubbling and steam comes out from around the lid. If I hold the lid tight against the pot, the water boils more vigorously. Is that not more pressure, roughly same temperature, and more boiling?

Sorry - I just looked up "pressure cooker" on how stuff works:

The reason foods have these instructions is because the boiling point of water changes with altitude. As you go higher, the boiling temperature decreases.
At sea level, the boiling point of water is 212 degrees F (100 degrees C). As a general rule, the temperature decreases by 1 degree F for every 540 feet of altitude (0.56 degrees C for every 165 meters). On top of Pike's Peak, at 14,000 feet, the boiling point of water is 187 degrees F (86 degrees C). So pasta or potatoes cooked at sea level are seeing 25 degrees more heat than pasta or potatoes cooked on Pike's Peak. The lower heat means a longer cooking time is needed.

Pressure cookers work in the opposite direction. A pressure cooker raises the pressure so that the water boils at a higher temperature. A typical pressure cooker applies 15 pounds of pressure, so the boiling point of water rises to 250 degrees F (121 degrees C) at sea level. The higher temperature means that foods take less time to cook.

I'm really confused now, though. I swear I was taught that putting contents under pressure will increase the heat of the contents. So when you pressurize something, does it both higher the boiling point and raise the temperature? If so, what's the part of the equation that keeps everything in check, i.e. what factor keeps anything under pressure from generating heat, increasing its own pressure, generating more heat, etc? Some things under pressure explode, but not all things.

Isn't space supposed to be something close to -273? So the whole liquids boiling thing means that the boiling point of any liquid (here on Earth) is effectively quite close to that in space? If I've got that right, it would seem like the whole-material-diffusion-in-a-vacuum things is quite close in nature to boiling?

 

[Hank Fletcher]

Okay, here's something else I've been wondering about for a long time now. Hydrogen and Helium are used in balloons because they're low in density, but (I'm presuming here) they provide some component of structure to inflate the balloon. If you had a very solid type of balloon, made of thick aluminum or something, and then sucked all the air, everything, out of it, would it float? I guess you could argue that it would collapse under the weight of the atmosphere, but if you took it very high, would it float up there?

Don't they use this principle in weather balloons? Near sea-level, they're practically droopy because they have a minimal amount of gas inside, but by the time they reach the limits of the atmosphere, the relative lower pressure outside the balloon makes the gas inside expand and fill the balloon to capacity (and then eventually boil?).

 

[t.o.]

I thought the floating is a matter of comparing two densities. i.e. Mass/Volume. In case the metal ball is very large and resulting in less density than the air around, I think it will float.

 

[Nigel Goodwin]

Isn't space supposed to be something close to -273?

A popular misconception, space doesn't really have a temperature - biggest problem for spacecraft and astronauts is getting rid of heat, not keeping warm. There are a number of ways of getting rid of heat, but in a vacuum only radiation works.

Bear in mind if you want to keep a hot drink hot you place it in a vacuum flask, a vacuum is just a very good insulator.

 

[audioguru]

A supercharger compresses liquid fuel.

No way, man!
Liquids do not compress.
A supercharger or a turbo compress the air so that more fuel can be added to it so the engine can blow its head or blow its head gasket off.
Or smoke the tires. Or get a speeding ticket. Or crash!

Kentucky Fried Chicken is cooked quickly in a pressure cooker. I wish the pressure is even higher so the higher temperature can melt that awful fat on today's chickens that are "porky".

The pork today hardly has any fat.

 

[Krumlink]

As awlays, google has the answer, as well as some goofy websites that are kind of disturbing:

Answer (for water):
https://www.physlink.com/Education/AskExperts/ae15.cfm?CFID=22184940&CFTOKEN=56872759

Goofy Website:
**broken link removed**

 

[Ambient]

I thought that your blood "boiling" always referred to the fact that at lower pressures the nitrogen in your blood simply gathers into bubbles, similar to steam bubbles in boiling water (but not caused by heat). That is why you do not screw around in a decompression chamber!

 

[Ambient]

A popular misconception, space doesn't really have a temperature - biggest problem for spacecraft and astronauts is getting rid of heat, not keeping warm. There are a number of ways of getting rid of heat, but in a vacuum only radiation works.

Bear in mind if you want to keep a hot drink hot you place it in a vacuum flask, a vacuum is just a very good insulator.

Hmmm... if this is true then the people who claim Apollo 13 (and the moon landings) was a farce have another piece of evidence. The astronauts supposedly had problems staying warm in the module.

 

[Krumlink]

would it look somthing like this ?
**broken link removed**

when nitrogen forms in your blood it is called the Bends, right? It is caused by surfacing too quickly from diving deeply. They have to then go into a decompression chamber to return to normal levels.

 

[t.o.]

I saw some one being executed by an electric chair poped his eyes off like this.

Constant=Pressure X Volume /Temperature.

 

[Krumlink]

Wowzers!

https://images.google.com/imgres?im...lient=netscape-pp&rls=com.netscape:en-US&sa=G

 

[Sceadwian]

Ambient, you must have not understood what Nigel was saying. The only method is radiation. Regardless of how well it's insulated the materials the space ship was made of still radiated a lot of energy outwards, and in space there was very little energy hitting the ship (at least when it's in the dark) soo all the energy bleeds off very quickly.