Questions tagged [electromagnetic-radiation]

Electromagnetic radiation (EM radiation, EMR, or light) is a form of energy released by electromagnetic processes. In physics, all EMR is referred to as light, but colloquially light often refers exclusively to visible light, or collectively to visible, infrared, and ultraviolet light.

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How much 'stronger' is water vapor than carbon dioxide, molecule-per-molecule, over the course of a day, in terms of global warming potential?

I have read, many times, that water molecules are far more effective than CO2 molecules at trapping heat... But, the 'relative G.W.P.' value of water vapor (or its 'radiative forcing') is not listed ...
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Does water really have strong EM absorption at 3 kHz in solid and 2 GHz in liquid? Why the huge shift?

While writing this answer to the question Transmitter receiver coil separation for Electromagnetic Terrain Conductivity Measurement I ran across this large PDF file of a book Soil and Environmental ...
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Why do molecules showing a pure rotational spectra require a permanent dipole?

I understand that pure rotational spectra only exist for molecules which have a permanent dipole moment. The common explanation is "so that they can interact with the E-field of the incoming ...
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Are the $+\leftrightarrow+$ and $-\leftrightarrow-$ methanol rotational transitions dipole-allowed?

I am quite confused about the origin and justification of the rotational selection rules of methanol, and I would appreciate any help or references. As far as I understand, there are three irreducible ...
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Grapes in a Microwave - Experiment

I am considering attempting an experiment in which one puts two, almost severed, halves of a grape in a microwave with a glass over it. To my knowledge so far, the grape halves act as focal point for ...
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Is there a material that turns from being electrically conductive to non-conductive irreversably upon exposure to some form of radiation?

For my project I am looking for a material which can turn from being electrically conductive to nonconductive (has to be irreversible) upon exposure to electromagnetic radiation (say UV). I tried ...
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Radiating chemical suggestion?

Given a flat and thin object laying on a table, such as a small piece of silver paper or a small piece of cardboard, I want to find a way to detect which face of it is facing up. The solution should ...
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How much heat is created by absorbent-type sunscreens?

I have a friend who claims her dermatologist told her than sunscreen was what was burning her skin. (I think it's much more likely that her rash/burn was either a sunburn, a skin reaction to some ...