It's the fundamental definition of the term. A propeller takes rotating torque and uses it to produce fluid flow. If you try to do that in reverse, you have a turbine. That's why we call them "wind turbines" and not "wind propellers", even though it may look just like a propeller to you.
It's the exact opposite of what you think. This is a fan car. The propeller pushes the car, the car drives the wheels, and the wheels drive the propeller. The tail wind means the propeller can produce more lift pushing the car forward than the wheels are producing friction, until inefficiencies in the linkages result in an upper limit.
Think of a windmill, and think of what happens to that windmill as you approach the speed of the wind. The velocity of air flowing over that windmill will approach zero, meaning the power being produced by that windmill will similarly approach zero. What you propose could be used to drive upstream against the wind, but not with the wind. Please try again.
Ignorance is the lack of knowledge. Stupidity is the inability to receive knowledge from those that are actually knowledgeable. gweihir used the term correctly.
Turbofans, on the other hand, also have, well, the fan part in front.
Yes, turbofans have propellers. But the engine on this hypothetical aircraft is a jet, not just a generic turbine. And even if the hypothetical engine here is a turboprop, the lift is NOT provided by the air the propeller moves, it is provided by the air moving over the wing due to the forward motion of the aircraft.
Not to mention a turbofan is still nothing more than a compressor. The compressor is used to generate pressure, and the pressure is then manipulated into a jet of high velocity air using a nozzle to generate reaction thrust. The only thing separating a turbofan from a turbojet is that much of what the fan compresses bypasses the combustion chamber, and is used to provide thrust directly.
Your words, they make no sense. A propeller is powered. It cannot be used to extract power. We call that an impeller, or turbine. The wheels power the propeller, or the wheels are powered by the impeller, you cannot have wheels powered by a propeller.
Actually, camber and thickness are more critical to an airfoil getting lift than angle of attack. Any fool with a basic understanding of aerodynamics knows those flat blades on a ceiling fan will stall out with just a couple degrees angle of attack, wasting huge amounts of energy. Your small scale demonstrations using a model with an absurd thrust-to-weight ratio does not apply to the real world. Your teacher should have learned the actual concepts she was trying to teach, rather than just reiterate something she got out of a book.
To be fair, if the treadmill is long enough and moving fast enough, it will produce a boundary layer that will envelop the plane in a high speed airflow, potentially fast enough to allow it to take off vertically, at least until it rises above said boundary layer.
No, the principles of Relativity (proper noun) ARE something specific to nuclear physics and other high energy endeavors. Technically, they apply everywhere, but we only care about them when energy levels are sufficiently high that they are of a meaningful scale. You're just talking about basic geometric reference frame transformations. The math is all the same regardless of your reference frame, it's just oriented a bit different.
Wind isn't pushing the craft forward. The propeller is pushing the craft forward. The wheels are powering the propeller. Wind is reducing the airspeed with respect to ground speed, thus reducing aerodynamic drag, giving an advantage that the craft can manipulate.
I went to high school in the 90s. I took my city's local public transportation home. When I felt up to it, I would run half a mile through the city to catch the early transfer and get home half an hour earlier. Biometricly secured school buses that drop you off in front of your home? Pussies...
It's not like you use an image of your iris or fingers to match against in a biometric scan. You have a program that algorithmically breaks the image down into a few key geometries features, so it can more easily be used in a fuzzy comparison during a scan. The information doesn't exist until you scan and process it.
They're not buying GMO seed. They can't stop, because they never started in the first place. This is not something that Monsanto is selling for use. It is a lab strain that showed up in the wild.
It's a similar problem, but at a significantly different scale. You're probably looking at a few hundred miles worth of cable at a couple Gs, as compared to 25k miles averaging half a G. Still, if you can manage to put several hundred miles worth of high tensile cable into orbit to pull off this maneuver, surely you could just as easily use that payload for dense lead shielding on your spacecraft instead. What ever happened to the concept of lining your spacecraft with your water and waste stores to use as shielding?
By definition, DRM exists to protect the content from the user. Following that logic, no user can ever implement any system that interfaces with DRM in a secure manner. DRM cannot be "supported by all", as it can only be supported by those vetted and licensed by the group managing the DRM mechanism. It has no right in an open standard, as you are not freely able to implement it.
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It's the fundamental definition of the term. A propeller takes rotating torque and uses it to produce fluid flow. If you try to do that in reverse, you have a turbine. That's why we call them "wind turbines" and not "wind propellers", even though it may look just like a propeller to you.
Go to an English teacher and ask them what a "proper noun" means.
It's the exact opposite of what you think. This is a fan car. The propeller pushes the car, the car drives the wheels, and the wheels drive the propeller. The tail wind means the propeller can produce more lift pushing the car forward than the wheels are producing friction, until inefficiencies in the linkages result in an upper limit.
Think of a windmill, and think of what happens to that windmill as you approach the speed of the wind. The velocity of air flowing over that windmill will approach zero, meaning the power being produced by that windmill will similarly approach zero. What you propose could be used to drive upstream against the wind, but not with the wind. Please try again.
Ignorance is the lack of knowledge. Stupidity is the inability to receive knowledge from those that are actually knowledgeable. gweihir used the term correctly.
Assuming the treadmill is not frictionless, and is of sufficient size, yes.
Turbofans, on the other hand, also have, well, the fan part in front.
Yes, turbofans have propellers. But the engine on this hypothetical aircraft is a jet, not just a generic turbine. And even if the hypothetical engine here is a turboprop, the lift is NOT provided by the air the propeller moves, it is provided by the air moving over the wing due to the forward motion of the aircraft.
Not to mention a turbofan is still nothing more than a compressor. The compressor is used to generate pressure, and the pressure is then manipulated into a jet of high velocity air using a nozzle to generate reaction thrust. The only thing separating a turbofan from a turbojet is that much of what the fan compresses bypasses the combustion chamber, and is used to provide thrust directly.
Your words, they make no sense. A propeller is powered. It cannot be used to extract power. We call that an impeller, or turbine. The wheels power the propeller, or the wheels are powered by the impeller, you cannot have wheels powered by a propeller.
Actually, camber and thickness are more critical to an airfoil getting lift than angle of attack. Any fool with a basic understanding of aerodynamics knows those flat blades on a ceiling fan will stall out with just a couple degrees angle of attack, wasting huge amounts of energy. Your small scale demonstrations using a model with an absurd thrust-to-weight ratio does not apply to the real world. Your teacher should have learned the actual concepts she was trying to teach, rather than just reiterate something she got out of a book.
To be fair, if the treadmill is long enough and moving fast enough, it will produce a boundary layer that will envelop the plane in a high speed airflow, potentially fast enough to allow it to take off vertically, at least until it rises above said boundary layer.
Helicopters take off vertically via thrust alone, and they typically do not have rocket engines.
No, the principles of Relativity (proper noun) ARE something specific to nuclear physics and other high energy endeavors. Technically, they apply everywhere, but we only care about them when energy levels are sufficiently high that they are of a meaningful scale. You're just talking about basic geometric reference frame transformations. The math is all the same regardless of your reference frame, it's just oriented a bit different.
Wind isn't pushing the craft forward. The propeller is pushing the craft forward. The wheels are powering the propeller. Wind is reducing the airspeed with respect to ground speed, thus reducing aerodynamic drag, giving an advantage that the craft can manipulate.
A "dud"?
Wouldn't that be a Dickian?
Where can I buy one of these fancy nuclear furnaces and stove tops?
I went to high school in the 90s. I took my city's local public transportation home. When I felt up to it, I would run half a mile through the city to catch the early transfer and get home half an hour earlier. Biometricly secured school buses that drop you off in front of your home? Pussies...
It's not like you use an image of your iris or fingers to match against in a biometric scan. You have a program that algorithmically breaks the image down into a few key geometries features, so it can more easily be used in a fuzzy comparison during a scan. The information doesn't exist until you scan and process it.
They're not buying GMO seed. They can't stop, because they never started in the first place. This is not something that Monsanto is selling for use. It is a lab strain that showed up in the wild.
I would love to see this 20kg solar blast furnace capable of refining, producing, and weaving aluminosilicate glass fibers from Martian regolith.
What about all that cosmic radiation? Watch out for those pesky oh-my-god particles....
It's a similar problem, but at a significantly different scale. You're probably looking at a few hundred miles worth of cable at a couple Gs, as compared to 25k miles averaging half a G. Still, if you can manage to put several hundred miles worth of high tensile cable into orbit to pull off this maneuver, surely you could just as easily use that payload for dense lead shielding on your spacecraft instead. What ever happened to the concept of lining your spacecraft with your water and waste stores to use as shielding?
Uh oh. You're breathing in radioactive Carbon-14 right now. You better hold your breath...
No. We read an article about how US limits on radioactivity at Superfund sites are ridiculously low compared to the allowable exposure limits.
By definition, DRM exists to protect the content from the user. Following that logic, no user can ever implement any system that interfaces with DRM in a secure manner. DRM cannot be "supported by all", as it can only be supported by those vetted and licensed by the group managing the DRM mechanism. It has no right in an open standard, as you are not freely able to implement it.