# Tag Info

4

Higher frequencies attenuate faster in air than lower frequencies. The further away a lightning flash the less high frequency components will reach your ear

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From measurements taken over the tropical Pacific Ocean, reported in Diurnal and Semidiurnal Variations of the Surface Wind Field over the Tropical Pacific Ocean (Deser and Smith, 1997), observe that The observed semidiurnal near-surface wind variations are dynamically consistent with the zonally averaged semidiurnal pressure field, which is forced ...

1

Because Pressure and Temperature are intensive properties. Intensive properties do not depend on mass or number of moles. Whereas Volume is a extensive property, so it is divided by n to make it an intensive property (often to facilitate calculations). http://en.wikipedia.org/wiki/Intensive_and_extensive_properties

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You are right: if the gas you are studying is not in a container, it is difficult to attribute a volume to it. The key here is to realize that on the scale of the atmosphere, temperature, pressure and density change - by a lot. So you can't think of "all of the atmosphere" as a single body of air with uniform properties - the properties change locally. As ...

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The Earth's atmosphere is mostly nitrogen and oxygen, both of whose behaviors are very close to ideal at the temperatures and pressures found in the atmosphere. Nitrogen, the dominant gas in the atmosphere, comes particularly close to exhibiting ideal behavior. Gaseous oxygen exhibits about a 3% departure at 20 atmospheres at standard temperature, with ...

2

Look at the definition of ideal gas . An ideal gas is a theoretical gas composed of many randomly moving point particles that do not interact except when they collide elastically. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics. One mole of an ...

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Instead of a short lighten stroke, the stroke traveled through several clouds for several miles, unseen by you. This is how you might get a long rolling thunder. There could also be several unseen strokes which the thunder overlaps to sound as one.

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The sky does not skip over the green range of frequencies. The sky is green. Remove the scattered light from the Sun and the Moon and even the starlight, if you so wish, and you'll be left with something called airglow (check out the link, it's awesome, great pics, and nice explanation). Because the link does such a good job explaining airglow, I'll skip ...

19

Note well: What we perceive as color is bit of a tricky subject. This is a different question, one that has been asked and answered multiple times at this site. Per the typical human eye response, sunlight at the top of the atmosphere is about as "white" as "white" can be. Some of that incoming sunlight is reflected back into space, some is absorbed by the ...

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The hand waving explanation in your question is called Rayleigh scattering Rayleigh scattering results from the electric polarizability of the particles. The oscillating electric field of a light wave acts on the charges within a particle, causing them to move at the same frequency. The particle therefore becomes a small radiating dipole whose radiation ...

5

The sun is technically green because the peak of its black body spectrum is near green wavelengths. When light scatters parallel to the plane of incidence (i.e., during the day time), it is blue-shifted. When light scatters perpendicular to the plane of incidence (i.e., sunset or sunrise), it is red-shifted. The light that is not scattered but makes it ...

0

If you use the barometric equation you find the final pressure. Since for the derivation of the barometric equation: $$P=P_0 \exp\left(\frac{gmh}{RT}\right)$$ You use the ideal gas equation and assume temperature to be uniform, there really isn't much you can do with that (AFAIK). However if you account for temperature decline and make the first ...

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Several nuclear devices have been detonated at high altitude i.e. effectively in space. The best known is probably the Starfish Prime test. A video of the detonation is available on Youtube. In vacuum the explosion is basically spherical, though turbulence develops in the expanding wavefront and that creates fine structure that makes it look like a hairy ...

2

No. The parcel of gas expands adiabatically as it rises. This makes it cool. Here's one way of looking at what happens: No heat is transferred to or from the parcel of gas (so, adiabatic). At the same time, the parcel of gas expands as it rises. That means the parcel is doing work on the external environment. The temperature of the parcel must drop to ...

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I know that air pressure and temperature are inversely proportional. You should not know that. This is the source of your misunderstanding. The ideal gas law, $PV=nRT$, can be rewritten as $P=\frac R m \rho T$, where $m$ is the average mass of a molecule in the gas and $\rho$ is the density of the gas. The first term on the right is a constant for a ...

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On this diagram, why is the atomspheric opacity shaped as it is? Different parts of the atmosphere are responsible for the shape of that curve. Electromagnetic radiation impinging on some object can be reflected by the object, absorbed by the object, or transmitted through the object. An ideal black body absorbs all incoming radiation, regardless of ...

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Observable simply means that with the right detector, we could see it. As you have realised, opacity refers to what percentage of the radiation is blocked. The thing is, we can 'see' radio waves - just not with our eyes. Our eyes are only sensitive to a very small range (on the diagram it's the rainbow). If you have something that can detect radio waves, ...

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Why can't we measure the pressure at 1000 m for different temperatures? Meteorologists certainly can do that, and in fact do do that, all the time. They use weather balloons, sounding rockets, and all other kinds of instrumentation to measure conditions in the atmosphere. The resulting picture is rather complex. Conditions vary with place, the seasons, ...

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For aviation purposes, standard atmosphere is considered to be dry air at mean sea level, at 15 degrees C (59F). It is true that pressure decreases with increasing altitude, and temperature usually does, but not always. It is not a simple relationship, because it depends on humidity, heat transfer from above and below, vertical circulation, horizontal ...

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Use Friis' formula http://en.wikipedia.org/wiki/Friis_transmission_equation to estimate the received power. Notice that it has the transmit and receive antenna gains and these are nearly ~1 for simple dipole (or monopole) antennas that are omni-directional in a plane perpendicular to the antenna current flow. Given the antennas the received power is ...

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Section 2.9 (bottom half on page 11) of this document describes why a 5GHz router suffers greater attenuation than a 2.4 GHz router, particularly so in residential and office settings. Attenuation is greater at 5 GHz than at 2.4 GHz for signals that need to pass through walls, doors, and glass. From the above reference: More energy per photon does not ...

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I have three answers to your question. I'll start with the short and snippy versions first: Why does the atmosphere move with the Earth? Because it already is. Wind. It isn't. At least not exactly. The air rotates with the Earth because of conservation of angular momentum. Because the atmosphere is already more or less rotating with the Earth, an ...

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