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First of all the Earth's radius is about $6.4\times 10^6\mathrm{m}$, while its orbital radius is about $1.5\times 10^{11}\mathrm{m}$: about $2.3\times 10^4$ times its radius: yes, it is a good approximation that the whole Earth is at the same distance from the Sun. Secondly, this is the flux passing per unit area of the imaginary shell: the flux per unit ...


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I don't fully comprehend why the positive (and therefore quicker) parts appear to be retarding and eventually making a N-like sawtooth wave? I wrote a more detailed answer at http://physics.stackexchange.com/a/139436/59023, but the basic idea is that the larger amplitude parts of the wave have a higher phase velocity than the lower amplitude parts. ...


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International Agency for Research on Cancer groups cell phone in group 2B, which is for possibly carcinogenic to humans. Not even probably. So, it is not that harmful . But, you can protect your by Electromagnetic shielding. You can figure out a way to connect conductive or magnetic materials either to your or the phone, but if you connect it to your ...


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Background The specific intensity or brightness, $I_{\nu}$, is defined as: $$ I_{\nu} = \frac{ dE }{ dA \ dt \ d\Omega \ d\nu } \tag{1} $$ where $\nu$ is the frequency, $dE$ the differential energy, $dA$ the differential area, $dt$ the differential time, $d\Omega$ the differential solid angle, and $d\nu$ the differential frequency. We can define a net flux ...


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The Albedo describes the fraction of radiation reflected for a given area of the surface. If you are combining albedos for different parts of the surface of a body, you need to weight them by their areas, for example consider albedos $\alpha_1$ and $\alpha_2$ corresponding to areas $A_1$ and $A_2$, then the effective albedo for the total area is: ...


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I've worked out a formula that assumes no absorption in the atmosphere, and that light is only backscattered. It takes into account the backscattering of the light reflected off the surface. In the diagram below: TOA is Top Of Atmosphere $\tau_a$ and $A_a$ are the transmittance and albedo of the atmosphere such that $\tau_a+A_a=1$ $A_s$ is the albedo of ...


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Ionization is not just to do with knocking electrons out of atoms and molecules. If there is enough energy available the bonds between molecules can be broken to form ions. Energies of 33 eV are equivalent to the extreme UV band of the electromagnetic spectrum. Energies of this magnitude can break up water molecules and produce free radicals (reactive ...


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I think the term "released" is applied a bit too liberally here: The underlying idea should be the following: As per your Chem 101 course, you need energy to ionize an atom. But the atom will not stay ionized, it will immediately attract an electron again. This electron will then release energy - the ionization energy. Since the original energy to ionize ...


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I think the figure of 33eV comes from the definition of ionising radiation i.e. electromagnetic radiation with an energy above around 10 to 33 eV (the boundary is somewhat vaguely defined). However gamma radiation from radioactive sources can be much, much higher energy than this. The mechanism is that a gamma photon is absorbed by an atom and produces an ...


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Neutrons and protons are hadrons and are identified as an isotopic spin 1/2 hadron called baryon. There are many hadrons, pions, kaons, detas, etc , and one of the quantum numbers that separates them is the baryon number. Protons and neutrons each have baryon number 1. Thus a neutron turning into a proton does not change the baryon number. Isobaric means ...



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