# Tag Info

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Limits can be fuselage to the tip of the wings :) !! As some user mentioned its just a force in total, nothing to worry on the limits over the integration. If one take it as a line just summing all lines will give the area and of course the force. For example if xxxx Newtons force in a single line and summing it over the sampled area (each sample is ...

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Pressure is isotopic (it acts equally in all directions) so it doesn't matter how the static pressure hole is oriented (it just happens that a hole in the tube sidewall is convenient and hence is tangential to the flow). Nevertheless the pitot tube must face into the flow in order to bring it to rest.

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There seems to be some confusion: Stagnation Pressure is likely what you are thinking of - it is in the direction of fluid velocity, and includes the dynamic pressure + the static pressure. The distinction is important. Stagnation pressure is a measure of the energy in the system. You can't measure stagnation pressure with a tangent hole. You use a ...

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The answer, according to John Denker at av8n.com is that the decrease in static pressure due to velocity is, to a first approximation, $1/2\rho v^2$ and $v$ is small compared to the speed of sound. It's small enough to neglect. As he says: As you increase your airspeed, the stagnation pressure goes up, but the static pressure does not.

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There is a very detailed analysis of the physics of spinning balls, torque and drag, in http://www.cim.mcgill.ca/~mpersson/docs/AeroSphere_Persson.pdf More simply, according to this earlier answer, in the case of a sphere spinning in place the torque experienced is given by $$\vec\tau = -8\pi R^3\eta\vec\Omega$$ but that result seems to be valid only ...

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The blade geometry and structural stability is less meaningfull when you have more blades. Means; if you have to to build the blades only from direct cutted materials without any airfoil-shape you have to use more blades. Thanks to Betz law, this doesn't even change the efficiency too much, and it's more or less only a investment cost factor. And, ...

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Could the phenomenon of vortex bursting be exploited to reduce wake turbulence? Well, it's the only way to get rid of the Turbelence. Turbulence is caused by vortexes and they obviously must burst, before they completely stop. My question is, what are the physical variables which promote or inhibit vortex bursting and, if they can be controlled, can this ...

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The article defines lift as a force vector perpendicular to the aircraft's path through the air, not the force vector needed to balance gravity. Similarly, thrust is considered a force vector parallel to aircraft's path. If you imagine an aircraft pitching up from level to vertical (and its flight path inclining accordingly), as its pitch increases, the lift ...

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Mainly because of surface tension, but ofcourse also because of Newtons laws. Water has a Surface tension of 72.8 mN/m, The unit, N/m can also be written kg/s^2 or J/m2 In this case the J/m2 is the most practical. The Smaller the hitting angle of the stone makes this area bigger providing more Energy to be returned on elastic collision. There is also ...

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If you would just calculate the Reynold number to Troposphere, say, 10 000 m thick. Kinematik viscosity of air is, say, 1.2 x10^-5 so you found that with Re 4000 you would have just need to have a 0.0000048 m/s velocity In praxis, though, this is not the case, but it's a stratified fluid system; ...

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As far as I know, there is no data to calculate the drag effects of the atmosphere at these speeds. The Pascal-B shot of Operation Plumbob did, apparently, launch a 1-ton steel plate at 6 times escape velocity. https://en.wikipedia.org/wiki/Operation_Plumbbob Nobody has the faintest idea of whether or not it actually made it out of the atmosphere, although ...

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As the humidity of the air increases, its density decreases, so the fan blades will have an easier time passing through the air. I doubt the fan blades move muchy faster, because they are synched to the motor, but perhaps the decrease in force to pass through the air leads to a louder fan. What have you observed?

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Downwind reaches are much faster - as seen during the last America's Cup. Simple reason: if the drag on the hull is low, you can get a significant "head wind" which you add to the actual wind vector to give the apparent wind. This apparent wind needs to be at a "sensible" angle to the boat - enough lateral component that it can still "push" the sail. The ...

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I'm not a physicist and I don't have equations to prove what I'm about to say and I could be dead wrong, but I've been thinking of this very question and it led me to this thread. I would argue the Bernoulli principle should act opposite to Magnus effect. The movement of rotation would create the high velocity, low pressure on the opposite side to where the ...

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