All Questions
Tagged with electromagnetic-radiation energy
162
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What is the solar radiative power on a clear sky day through a surface which is parallel to the sun's incidence on Earth?
Assuming that the solar power through the incident surface is known. How can we calculate or estimate the radiation through the parallel surface assuming a clear sky?
Looking for watts per square ...
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Absorption and emission spectrum
I was wondering how do you see a spectrum when light is passed through a substance. Like most of the substances we use are opaque, so how does light pass through them without being reflected? Also ...
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Why don't the delocalised electrons in a metal emit light when they hit an atom and change their velocity very quickly (i.e. accelerate)
We know that in metals there is a sea of delocalised electrons which can freely travel around the lattice of metal ions and that these delocalised electrons move around at large speeds, sometimes ...
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Can a region of electromagnetic waves alone be considered a thermodynamic system? Can work and heat interactions be made sense for them?
Consider an ideal antenna producing coherent radio waves, and suppose the waves are not received by any body (they are sent off to space). Can we say a work interaction/transfer has been done? Or is ...
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What fraction of the universe's energy is contained in photons?
From each point in the universe, the light of billions of stars, galaxies, supernovae etc. can be detected. So there seems to be a lot of energy/momentum "in flight".
Is it possible to ...
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What happens to light absorbed by a body with color?
As everyone knows, an object with color appears that way because it reflects its specific color(s). Textbooks tell us other colors are absorbed. Now, here's the question: what happens to the absorbed ...
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How big is light pressure as a fraction of light energy?
Light hitting a surface impart a force on the surface, often called "radiation pressure". My question is, given a perfectly reflective surface, if light hits it at 90° to return in the ...
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What is the origin of energy emitted as radiation by an electrically charged object stationary around a massive object?
Einstein's special relativity tells us that laws of physics are the same in all
intertial frames. General relativity futher extends this by stating that
reference frames that are in free fall around ...
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Using CRT electron gun [closed]
I am a high-school student working with CRT electron gun. I want to make a setup using a CRT gun of an old television set where the beam will hit a target metal. I am making this setup at my home. I ...
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Energy of an electromagnetic wave
The total energy density $(U)$ of an electromagnetic wave is given by the equation
$$U=\frac{1}{2}\epsilon_0{E_0}^2+\frac{1}{2}\frac{{B_0}^2}{\mu_0}\tag{1}$$
Also quantum energy $(E)$ of a photon in ...
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Origination of electromagnetic wave energy
Please correct me if I am wrong in my statements
While it is said that electromagnetic waves are formed by the oscillation (acceleration) of charges which forms 'kinks' in their electric field which ...
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How can I calculate the energy of Electromagnetic wave for specific range of wavelength?
I have captured a wide bandwidth of electromagnetic waves (E and B fields) in the simulation. I would like to calculate the energy within a specific bandwidth. How can this be achieved? Which method ...
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Why is Wien's Approximation accurate for wavelengths 0 to Max?
I'm currently reading "Robert Eisberg, Robert Resnick - Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles", specifically Problem 23 in Chapter 1. The problem is shown below.
...
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How to Measure Energy of a Electromagnetic Wave accounting also for frequency?
We know a way of measuring energy of a electromagnetic wave is the Poynting vector, which is independent of the frequency. But let's say we want to make two different electromagnetic waves, with ...
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Interpretation of watts per square meter for intensity of radiation
The energy that an electromagnetic field can deliver to a system is proportional to the square of the field. However, we use the terminology watts per meter square to represent the amount of energy ...
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