All Questions
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questions
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Does $E^2=(mc^2)^2+(pc)^2$ hold for light travelling in an optically dense medium?
The rest mass of photon $m_0=0$ and photon travels at the speed of light in vacuum. So the energy of photon in vacuum is given by $$E_{vacuum}^2=(m_0c^2)^2+(pc)^2=(pc)^2$$ $$E_{vacuum}=pc=\gamma m_0c^...
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How long will the light exist inside the sphere?
Ok, so let's say we have a very thick, but hollow, metal sphere. The inside of the sphere has a radius of 100 meters. The sphere also has a door that can be opened and closed and when closed makes an ...
- 281
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Photon energy - momentum in matter
$E = h\nu$ and $P = h\nu/c$ in vacuum.
If a photon enters water, its frequency $\nu$ doesn't change.
What are its energy and momentum: $h\nu$ and $h\nu/c$ ?
Since part of its energy and momentum have ...
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