Strange question for my latest invention

[arkain101]

Question:

How fast does an object need to travel through a generally low altitude (1000feet above sea level) in order to have the air contain close to the same consistancy still water. This means to have the same push force with your hand in the air as you would in still water.

 

incase you are wondering..

The invention is a new concept of transportation for high speed water travel and extremely high velocity air travel. So fast so, that I would not be suprised for it to allow one to launch into sub-orbit from the momentum carried in the atomosphere.

[Boerseun]

This is a bit of a non-question.

 

Are you asking about the velocity an object needs to achieve in order for the air in front of it to have the same density as water?

 

If so, there are a lot of variables:

 

First of all, it depends on the airodynamics of the object, i.e. the physical design. A ball would have to fly a lot faster than a brick to achieve the same density. A bullet would, of course, need to travel even faster, seeing as it's more conical than a ball, and the surface area presented is a lot smaller in relation to the object volume.

Apart from that, it also depends on ambient temperature, air pressure (although I would assume sea-level, seeing as you mentioned an upper limit of 1000ft). I suppose this question is unanswerable unless you could supply the design, air-tunnel tests and analysis of the specific design, etc.

 

I suppose long before the density will approach that of water, friction will burn your object away, ala meteorites etc.

[arkain101]

Here is my meaning.

 

If you hold up surfboard to a stream of water coming out of a tube above you at 1mph.. how fast would air need to travel to push as hard?

 

I once hear that water has 20 times the power of wind at equal velocity. Not sure on that though.

[GAHD]

I'd think the calculation would go something like (Density of air) / (density of water) = (ratio of conversion for the water tables to apply). I know some guy did the math for spheres in a medium with x density vs gravity, which you may be able to appy to some degree, but I cannot recall his name and would need to check the books again to get it for you. If you know functions and can figure out a way to describe your design as a function, you could probably come close to guessing it's potential; but nothing ever really beats physical experimentation.

[arkain101]

Yea I am not ready for the mathematical apsects of these things. I have very good of experience in physical know how of the mechanical aspect of things.. and is more or less the way I develope any such ideas, although, I would prefer not to mention any of this untill I get a result out of one of these ideas.

Mainly I just wondered a simple question, of how fast does a volume of air need to blow against, say a board, to reach the same pushing force as water at for example 1m/s. I once heard on a televisions how about how a wave moving at 10mph has the force of 200mph winds? So this is the question I am curious about.