Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Cuey on 27/07/2006 11:31:15
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Im not sure that this is the right place but im new here so sorry if it is in the wrong place!
I am doing a little project and i need to know what wind is, where it comes from etc.
I have an idea but i may be way off! The only thing that i can come up with is that wind is caused by kinetic energy passed from molecule to molecule. The more kinetic energy, the stronger the wind. If this is right, it would explain why when you blow on something, it creates wind! (The heat energy from your breath is changed into kinetic) Also if this is correct, does that mean that in a true vacuum wind cannot exist? But then theres solar wind?
I'm confused! Any help would be greatly Appreciated as it would help me to better understand mt project.
E=MC2 is wrong!!!
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quote:
Originally posted by Cuey
Im not sure that this is the right place but im new here so sorry if it is in the wrong place!
I am doing a little project and i need to know what wind is, where it comes from etc.
[:)]
Hi, Cuey.
I even dont know is this a wrong place put this is a place where, i think, is many scient-interesting peopple read and talk through this forum.
Question is quite easy and otherwice difficult. Of cource wind can born many several reasons but one is that because wind is air-matter-flowing process, then must start to thing what things can start to push air-matter.
Basically wind is air-matter motion process.
Example.
Our lungs can cause small wind-effect. Air-matter flows from our lungs to out and air start to flow.
Example.
Different temperature at room floor and roof can cause wind-effect if room wall is somewhere holes so that air also can come in and out of room.
Also if you have not notice yet, the sea-land wind effect it quite common wind-effect. If sea and land has different temperature then there is. hmm. how i say, sea-wind or what is that english name of that wind process?
Example.
Flowing river can cause wind-effect so that water flow and it push air-matter also to flow with it.
Otherwice, example.
Big trees can brake wind-speed.
What is wind?
Easy answer.
Air-matter flowing process.
Difficult section.
What different things cause wind and how nature-process basically control wind-effect? That difficult area, there is many influences and different things, so good luck to your project.
"Without winds clouds dont travell."
[:)]
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Thanks that has helped! I sort of understand it now. But does that mean that wind cannit exist in a true vacuum? Because if wind is caused by particals of air flowing from an area of high pressure to an area of low pressure, then in couldn't take place in a vacuum! Is that right or am I way off?
Also what about a fan? How does a fan create wind?
E=MC2 is wrong!!!
-
quote:
Originally posted by Cuey
But does that mean that wind cannit exist in a true vacuum?
Also what about a fan? How does a fan create wind?
[:)]
Of cource. True vacuum dont has air-matter.
Example, surface of moon dont has air-matter and therefore there is no air-matter-wind.
Fan push air-matter to flow like your hand also if you move your hand fast.
[:)]
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cheers that helped alot!
E=MC2 is wrong!!!
-
wind is a group velocity of particles in a gas in a common direction.
A gas is the simplest state of matter where neutral particles just move freely about in space and bump into each other without sticking together In order to remain a gas all the particles need to have some energy in that they are all moving quite quickly
to give you an idea of the speeds involved: in air at room temperatue the molecules are moving at about 500 metres per second travel about one tenthousanth of a centimetere before they hit another gas molecule and hit about 5 thousand million other molecules every second. Note also that the molecules are travelling faster than the speed of sound in air which is about 330 metres per second.
Now temperature is defined by the speed that the molecules are travelling (or their kinetic energy if you prefer it)
Other important properties of a gass are if you compress it it gets hotter and denser (because the molecules hit the moving surface of the piston and speed up a bit and are closer together ) conversely if you allow it to expand a bit it gets ccoler and less dense.
Clearly high pressure gas will escape from a hole into a low pressure area and create a common velocity or wind.
Now we come to the atmosphere. the pressure of the gas at ground level is just caused by the weight of all he gas higher in the atmosphere bearing down upon it and in quiet conditions it reaches a stable state as you get higher the pressure is less (because there is less gas pressing down) it is also cooler because as it is stable a bit of gas that moves upwards must expand and cool down. this stable temperature gradient is known as the adiabatic lapse rate and is about one degree f for evry 300 ft (i think)
Now sunlight travels through clear air without having much effect but when it hits the ground most of it is absoebed and it heats up the ground this in turn heats up the gas near the ground and makes it expand and get less dense because the molecules are moving faster this them makes the gas rise because it is less dense than its immediate surroundings and as it rises more gas flows in from the sides creating the wind.
There are a great deal of other complexiries about how bigh the lumps of gas are likethat are rising are likely to be and what happens when the cool down enough to allow water vapour in the air to condense and form clouds but that's another story.
Learn, create, test and tell
evolution rules in all things
God says so!
-
quote:
Originally posted by Cuey
Im not sure that this is the right place but im new here so sorry if it is in the wrong place!
I am doing a little project and i need to know what wind is, where it comes from etc.
[:)]
Hi, Cuey.
I even dont know is this a wrong place put this is a place where, i think, is many scient-interesting peopple read and talk through this forum.
Question is quite easy and otherwice difficult. Of cource wind can born many several reasons but one is that because wind is air-matter-flowing process, then must start to thing what things can start to push air-matter.
Basically wind is air-matter motion process.
Example.
Our lungs can cause small wind-effect. Air-matter flows from our lungs to out and air start to flow.
Example.
Different temperature at room floor and roof can cause wind-effect if room wall is somewhere holes so that air also can come in and out of room.
Also if you have not notice yet, the sea-land wind effect it quite common wind-effect. If sea and land has different temperature then there is. hmm. how i say, sea-wind or what is that english name of that wind process?
Example.
Flowing river can cause wind-effect so that water flow and it push air-matter also to flow with it.
Otherwice, example.
Big trees can brake wind-speed.
What is wind?
Easy answer.
Air-matter flowing process.
Difficult section.
What different things cause wind and how nature-process basically control wind-effect? That difficult area, there is many influences and different things, so good luck to your project.
"Without winds clouds dont travell."
[:)]
-
Thanks that has helped! I sort of understand it now. But does that mean that wind cannit exist in a true vacuum? Because if wind is caused by particals of air flowing from an area of high pressure to an area of low pressure, then in couldn't take place in a vacuum! Is that right or am I way off?
Also what about a fan? How does a fan create wind?
E=MC2 is wrong!!!
-
quote:
Originally posted by Cuey
But does that mean that wind cannit exist in a true vacuum?
Also what about a fan? How does a fan create wind?
[:)]
Of cource. True vacuum dont has air-matter.
Example, surface of moon dont has air-matter and therefore there is no air-matter-wind.
Fan push air-matter to flow like your hand also if you move your hand fast.
[:)]
-
cheers that helped alot!
E=MC2 is wrong!!!
-
wind is a group velocity of particles in a gas in a common direction.
A gas is the simplest state of matter where neutral particles just move freely about in space and bump into each other without sticking together In order to remain a gas all the particles need to have some energy in that they are all moving quite quickly
to give you an idea of the speeds involved: in air at room temperatue the molecules are moving at about 500 metres per second travel about one tenthousanth of a centimetere before they hit another gas molecule and hit about 5 thousand million other molecules every second. Note also that the molecules are travelling faster than the speed of sound in air which is about 330 metres per second.
Now temperature is defined by the speed that the molecules are travelling (or their kinetic energy if you prefer it)
Other important properties of a gass are if you compress it it gets hotter and denser (because the molecules hit the moving surface of the piston and speed up a bit and are closer together ) conversely if you allow it to expand a bit it gets ccoler and less dense.
Clearly high pressure gas will escape from a hole into a low pressure area and create a common velocity or wind.
Now we come to the atmosphere. the pressure of the gas at ground level is just caused by the weight of all he gas higher in the atmosphere bearing down upon it and in quiet conditions it reaches a stable state as you get higher the pressure is less (because there is less gas pressing down) it is also cooler because as it is stable a bit of gas that moves upwards must expand and cool down. this stable temperature gradient is known as the adiabatic lapse rate and is about one degree f for evry 300 ft (i think)
Now sunlight travels through clear air without having much effect but when it hits the ground most of it is absoebed and it heats up the ground this in turn heats up the gas near the ground and makes it expand and get less dense because the molecules are moving faster this them makes the gas rise because it is less dense than its immediate surroundings and as it rises more gas flows in from the sides creating the wind.
There are a great deal of other complexiries about how bigh the lumps of gas are likethat are rising are likely to be and what happens when the cool down enough to allow water vapour in the air to condense and form clouds but that's another story.
Learn, create, test and tell
evolution rules in all things
God says so!