Photon Energy: Frequency and Height in a Well

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A photon of frequency f retains its energy as hf when falling into a well of height x, as it has no mass to gain gravitational potential energy. The discussion emphasizes conservation of energy, suggesting that the photon would need to gain energy equivalent to a mass of hf/c^2 to maintain balance. The idea that a massless photon could gain energy from falling contradicts the principles of energy conservation. Therefore, the energy of the photon remains constant regardless of its position in the well. The conclusion reinforces that a photon's energy does not change due to gravitational effects.
Gyroscope

Homework Statement


A photon of frequency f falls in a well x meters of height. What is the energy of the photon when it is at the bottom of the well.

The energy of a photon is hf. It would gain mgx for falling in the well, but since his mass is zero, the energy remains the same. Isn't it?


Homework Equations





The Attempt at a Solution

 
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If you think about conservation of energy, it would clearly have to gain the same amount of energy as a mass of size hf/c^2. Otherwise, converting energy to mass, dropping it and converting back to energy would leave you with a puzzling balance sheet.
 

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