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1

Your curve has two components in it: Actual solar intensity per unit area (affected by atmospheric conditions, that is the probability that the sunlight is not scattered or absorbed on its path through the atmosphere) The projection of the sunlight onto your collector: if your collector is facing in a particular direction, the angle of the normal of the ...


2

You'll need two things, the solar zenith angle $\theta$ and the air mass $AM$. The zenith angle is given by $$\cos\theta = \cos\phi \cos \delta + \sin\phi \sin\delta \sin h$$ where $\phi$ is your latitude, $\delta$ is the declination of the Sun, and $h$ is the hour angle. You should know your own latitude. The declination of the Sun can be found on a ...


5

It is so possible that it actually happens on Earth, where I suppose we are both breathing. I think you should read the mirage page of Wikipedia (where I learned all I am saying here) as this can actually happen on our planet. It is called a superior mirage, and happen when you have temperature inversion, with a ground colder than the air above. The ...


0

Lightning takes a largely random path. This is apparent if you watch the process before the strike: Watch the video -- it is amazing. A somewhat less amazing illustration of the process: This is from NOAA, via Wikipedia. These leaders feel out a path between two objects (like the cloud and Earth), sometimes branching, traveling in complex paths. ...


41

Clean dry air lets sunlight through; dirty moist air scatters it. Aerosols (small air borne particulate contamination) are more prominent near areas of dense population - due to power plants, cars, fires, ... These particles form nucleation sites for moisture - and these small water drops become very effective scatterers of sunlight. The humidity is high ...


3

I'll use this answer to provide some information that's mostly orthogonal to what Phonon said. As Phonon pointed out, the speed of sound depends on temperature, not pressure. It's cold on the top of high mountains, so the speed of sound would tend to be lower. Some mechanisms for sound production have a frequency that depends on the speed of sound, and ...


3

There more sides to this scenario that you're considering. Firstly, if we are assuming that the temperature is the same at sea level and on the high mountains, then the speed of sound doesn't actually change, as a constant temperature will take care of the air pressure-density ratio. $$c = \sqrt{\kappa \frac{p}{\rho}} $$ Where $p$: static air pressure, ...


0

Assuming absolutely no wind there will still be areas of turbulence, things will still be transferring heat to the air causing it to move, it doesn't take much motion for air to become turbulent because of its low viscosity. Viscosity will dampen any instability, so low viscosity means its easy for instability and turbulence to occur


1

No. Atmospheric pressure is 14.7 lb/sq inch. That is, the air in a 1 inch square column from the ground to outer space weighs 14.7 lb. A 1 inch square column of water 32 feet tall also weighs 14.7 lb. A column as deep as the ocean weighs tons. This means there is several hundred times more water than atmosphere. If you heated the ocean until it boiled, ...


1

The speed of a molecule is given by: $$V_{rms}=\sqrt{\frac{3k_BT}{m}}{\tag1}$$ with v in m/s, T in kelvins, and m is the molecule mass (kg). The most probable speed is 81.6% of the rms speed, and the mean speeds 92.1% (isotropic distribution of speeds). The mass of an oxygen molecule is $5.313\times 10^{-26}$ kg. This gives $v_{rms}$ a value of about ...


2

Yes, the general process of losing gas molecules is possible. It's called atmospheric escape. The escape speed mechanism you mentioned is just one way in which it happens. Since lighter molecules move faster, they tend to be nearer the escape velocity. The Earth has lost (and continues to lose) hydrogen over the course of its history due to this. Oxygen is ...



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