Photon Energy when Doppler Shifted

Thread starter smyri
Start date Apr 13, 2005
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Doppler Energy Photon

In summary: This is because the momentum of the photons (and the energy they contain) is the same in both frames. However, when you try to create an electron and photon pair, the energy of the photon is going to be different in the two frames. This is because the momentum of the photon is a function of its energy, and the energy of the electron is a function of its momentum.

May 2, 2005

smyri

Great answer...perfecto! Thanks a million Ich. Yes, I see it now...the smaller dm, when moving, is more massive!

<h2>1. What is photon energy when Doppler shifted?</h2><p>Photon energy when Doppler shifted refers to the change in energy of a photon due to the Doppler effect. The Doppler effect is the change in frequency and wavelength of a wave when the source of the wave is moving relative to the observer. This change in frequency results in a change in energy of the photon, which is directly proportional to the frequency of the wave.</p><h2>2. How does the Doppler shift affect photon energy?</h2><p>The Doppler shift affects photon energy by changing the frequency of the wave. If the source of the wave is moving towards the observer, the frequency of the wave will increase, resulting in an increase in photon energy. Conversely, if the source is moving away from the observer, the frequency will decrease, leading to a decrease in photon energy.</p><h2>3. Can Doppler shifting change the color of light?</h2><p>Yes, Doppler shifting can change the color of light. This is because the color of light is determined by its frequency, and the frequency can be changed by the Doppler effect. For example, if a light source is moving towards an observer, the frequency will increase, causing the light to shift towards the blue end of the spectrum (blue shift). If the source is moving away, the frequency will decrease, resulting in a shift towards the red end of the spectrum (red shift).</p><h2>4. What is the equation for calculating photon energy when Doppler shifted?</h2><p>The equation for calculating photon energy when Doppler shifted is E = hf, where E is the energy of the photon, h is Planck's constant (6.626 x 10^-34 joule seconds), and f is the frequency of the wave. This equation shows that photon energy is directly proportional to frequency, meaning that any change in frequency due to Doppler shifting will result in a corresponding change in photon energy.</p><h2>5. How is Doppler shifting used in astronomy?</h2><p>Doppler shifting is used in astronomy to study the movement and properties of astronomical objects. By measuring the Doppler shift of light emitted from stars and galaxies, scientists can determine their relative motion and the presence of objects such as planets and black holes. Doppler shifting is also used to study the expansion of the universe and to detect the presence of exoplanets.</p>

1. What is photon energy when Doppler shifted?

Photon energy when Doppler shifted refers to the change in energy of a photon due to the Doppler effect. The Doppler effect is the change in frequency and wavelength of a wave when the source of the wave is moving relative to the observer. This change in frequency results in a change in energy of the photon, which is directly proportional to the frequency of the wave.

2. How does the Doppler shift affect photon energy?

The Doppler shift affects photon energy by changing the frequency of the wave. If the source of the wave is moving towards the observer, the frequency of the wave will increase, resulting in an increase in photon energy. Conversely, if the source is moving away from the observer, the frequency will decrease, leading to a decrease in photon energy.

3. Can Doppler shifting change the color of light?

Yes, Doppler shifting can change the color of light. This is because the color of light is determined by its frequency, and the frequency can be changed by the Doppler effect. For example, if a light source is moving towards an observer, the frequency will increase, causing the light to shift towards the blue end of the spectrum (blue shift). If the source is moving away, the frequency will decrease, resulting in a shift towards the red end of the spectrum (red shift).

4. What is the equation for calculating photon energy when Doppler shifted?

The equation for calculating photon energy when Doppler shifted is E = hf, where E is the energy of the photon, h is Planck's constant (6.626 x 10^-34 joule seconds), and f is the frequency of the wave. This equation shows that photon energy is directly proportional to frequency, meaning that any change in frequency due to Doppler shifting will result in a corresponding change in photon energy.

5. How is Doppler shifting used in astronomy?

Doppler shifting is used in astronomy to study the movement and properties of astronomical objects. By measuring the Doppler shift of light emitted from stars and galaxies, scientists can determine their relative motion and the presence of objects such as planets and black holes. Doppler shifting is also used to study the expansion of the universe and to detect the presence of exoplanets.