# Tag Info

## New answers tagged air

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Both turbines and motors can be used to turn an electric generator which produces electric power. I will exclude electric motors for this short overview. Both turbine and motor work on an operating fluid, the so-called working fluid. A turbine is continuously operating on the fluid, while a motor operates intermittently in strokes. Most modern cars use ...

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For the case of the nuclear generating plant, the difference between a motor and a turbine is a bit more subtle. In the nuclear generating plant, high pressure steam is generated by the heat of the nuclear reaction, and this high pressure steam is sent to a turbine. The turbine is connected via a shaft to a generator (which in some cases, can be a motor ...

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I see where you're trying to get to. So let me just jump right in with the textbook nomenclature. You are interested in the distinction between a device doing work versus having work done on it. What you might not have realized is that a turbine and a motor are in two completely different families. Let me lay out the distinctions here: A pump does work, ...

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A turbine is machine in which the kinetic energy of a moving fluid is converted to mechanical power by the impulse or reaction of the fluid with a series of buckets, paddles, or blades arrayed about the circumference of a wheel or cylinder. The mechanical power typically has the form of a torque on a rotating axis. A motor is generic term for a machine ...

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Assuming that the pressure change across the cone is small (e.g., no significant density changes for the flowing gas), use the continuity equation. With constant density, this simplifies to $A_1 \cdot v_1 = A_2 \cdot v_2$, where $A$ is the cross sectional area of the flow stream and $v$ is the velocity of the flow stream. If you additionally need the ...

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This is actually not a completely settled question, so don't feel too bad if you don't understand it in every detail! It's also possible that the cause is not the same in all situations, and be aware that my explanation is not universally accepted, but here's my interpretation: There are actually two interacting phenomena going on: the formation of the ...

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So the vortex street appears as the stream goes faster and faster: the stream obeys Newton's laws, "objects in motion tend to stay in motion unless acted on by a net force." The force that keeps the stream laminar around the cylinder is fluid pressure formed by the viscous forces of the fluid, which means there is a pressure gradient and a region of low ...

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A few things happen. One, the paper would bend, but lets pretend it's rigid, what happens when you lift. Your assumption is correct, air moves very fast, reducing but not completely eliminating the difference in air pressure between above and below. Air (molecules) moves at about 1,000 miles per hour. http://www.phy.mtu.edu/~suits/SpeedofSound.html ...

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Atmospheric pressure has nothing to do with it as you have not created a seal. You just have more surface area and more resistance. Karate chop versus lift is just speed. If you suspended the paper (assuming it would hold its shape) on fulcrum (no surface below) you would have the same effect. Ruler alone and enough seed and you could snap it. In a pure ...

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The average speed of the molecules depends on the temperature, not the pressure. That drives the energy available from collisions. On average, there is no more energy available at high pressure than at low pressure. At higher pressures, there will be more collisions, so ones at the top end of the energy spectrum become more common (as do all the others). ...

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If the cube is sealed, doesn't expand and the temperature doesn't change, the pressure inside the cube will remain at 14.7 psi. That pressure is applied to all 6 sides continuously, simultaneously. Pressure in a sealed container will depend only on the volume and the temperature, not the number of sides, nor the external pressure. On the other hand, there ...

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Sometimes I feel Wikipedia is a funny place... In the article you quote they provide a calculation from our patent application (see, e.g., http://akhmeteli.org/wp-content/uploads/2011/08/vacuum_balloons_cip.pdf ) proving that a homogeneous shell made of any existing material cannot be both light enough to float in air and strong enough to withstand ...

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The maximum change of pressure caused by a sound wave is its pressure amplitude. This would be the difference between high and low pressure areas in the sound wave. When sound is measured in pascals, however, for the purpose of computing decibels by comparing with other sounds, it's just the high pressure against the measuring surface, to the extent that ...

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Actually no because to set up a sound wave you push on some particles and they in turn push adjacent particles.So all you can try is pushing the first set of particles harder,but eventually they will collide with adjacent ones.So you ending up producing oscillations instead of collective motion.

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The answer is: not much. The usual analogy is waves at the beach. You can see a long line of waves rolling towards the land, but the water never actually moves across the land. Waves, whether water or sound, transmit energy by passing it along from one particle to the next. The medium itself oscillates but doesn't really go anywhere. There are ...

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Sound waves are changes in the pressure density of air. In other words, the air is already moving. A fan makes a sound when it strikes air because it's forcing it together and then it rebounds into adjacent air which undergoes yet another compression and expansion.

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Related question on EE: Does perfect insulation exist? (especially the part about vacuum) Insulators and conductors The property of a material to carry charges from one point to another is what electric current is. The difference between insulators and conductors lies in the electron band structure they posses. In conductors the Fermi-level ...

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