Recent content by Raptor01601

So when they talk about inviscid flow, are they just talking about the shear stress potion of the collision? Even in inviscid flow you would still have to have collsions, otherwise how would pressure be comunicated to other parts of the fluid? Sound is also comunicated (propagated) through...

Does anybody know of a book that addreses/talks about how Prandtl showed that an aircraft passing overhead will leave a "footprint" on the Earth in the form of an extremely small pressure change over a huge area?

I have been reading a number of aerodynamic texts, and it seems that everything in a fluid (gas) is transmitted by molecular collisions. Pressure is a result of molecules colliding with each other and the walls of a container Viscosity is caused by collisions between molecules in layers...

Yes, I'm familiar with the inverse square law of gravitation, I don't think that was the "crux" of the question. However, I'm still waiting to see if someone could explain to me how Prandtl fiqured out that an aircraft passing overhead will leave a "footprint" on the Earth equal to it's weight...

In a Vacum all objects have the same aceleration..that of gravity..32.2 fps^2 (on earth) I believe that Newton showed that Inertial mass and gravitational mass are the same thing. an object that has more mass in a gravitational field also has more force (weight) A greater force acting on a...

World Jumping day? You have got to be kidding... First of all, when you jump, you push down on the earth, and in theory the Earth moves opposite (there would be no way to detect such a small motion) However, also from theory, when you come back down, the Earth acelerates up to meet you...

Yeah, I have been plugging some numbers...and I came out with the following The Mass of the Earth is 4.105 X 10^23 slugs A 100,000,000 pound force acting on the Earth for 100,000,000 years would change the velocity of the Earth by .6 miles per hour

Sure, as I stated that there is usually someone going east when you are going west. But, that is not guaranteed. But that means that there is no time constraint, as what goes up, does not have to go come down right away. Such as an airplane, which can stay aloft for hours, and land thousands...

Ok...Just a thought model When an aircraft is in flight, the Earth pulls on the airplane (weight). The wings generate lift to support the weight. However, the aircraft is also pulling up on the Earth with the same force. So, techincally the Earth has momentum imparted to it in the...

Thanks...so if I had a really sensitive pressure gauge at the top and bottom of the cylinder, would I see a periodic pressure fluctuation? Even after the piston has stopped moving, as the "momentum flow" travels back and forth to the top and bottom of the cylinder?

Ok...this is a thought model to help me understand some things you have a cylinder with a gas in it. You also have moveable piston. I move the piston into the cylinder, compressing the gas by 25% of the original volume. I know the pressure of the gas will increase for two reasons...

Ok.. In a gas, pressure is caused by molecular collisions with each other and with the walls of whatever container they are in. These velocitys are random velocitys in the Vx, Vy, and Vz directions. Temperature is a measure of the average translational kinetic energy. If you have two...

[ I thought the rule was that energy is dissipated (turned into heat) by viscosity. Momentum is "spread out" by viscosity I think that spread out and transferred mean the same thing here. I realize that you could probably spread out the momentum so much that you no longer have a...

I know that you can dissipate the energy, turning it into heat, but you can not dissipate the momentum. Also, I think Prandtl showed that an aircraft at altitude will leave a "footprint" which would be extremely hard to maesure because it would be a really small pressure change over a huge...