Newton's kinetic energy vs Planck's Energy?

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SUMMARY

The discussion centers on the relationship between Newton's kinetic energy formula, E=1/2mv², and Planck's energy formula, E=hv. Newton's formula applies to objects with mass, where energy increases exponentially with velocity, while Planck's formula pertains to photons, with energy increasing linearly with frequency. The connection between these formulas can be explored through concepts like the photoelectric effect, where the energy of a photon can be calculated by combining the kinetic energy of an electron and its bond energy. Understanding these differences is crucial for comprehending energy dynamics in classical and quantum physics.

PREREQUISITES
  • Understanding of Newtonian mechanics, specifically kinetic energy.
  • Familiarity with quantum mechanics, particularly Planck's constant and photon behavior.
  • Knowledge of the photoelectric effect and its implications in physics.
  • Basic grasp of the Doppler effect and its impact on frequency and velocity.
NEXT STEPS
  • Research the photoelectric effect and its mathematical formulation.
  • Study the implications of massless particles in quantum mechanics.
  • Learn about the Doppler effect in relation to light and sound waves.
  • Explore the concept of rest mass and its relevance to photons.
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Students and professionals in physics, particularly those interested in the intersection of classical mechanics and quantum theory, as well as educators looking to explain the differences between kinetic energy and photon energy.

lenfromkits
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Formula for energy:

E = hv (where v=frequency; h=Planck's constant)

and

E= 1/2mv2 (New's kinetic energy).

How are these two formulas related? For starters, according to Newton, energy here increases exponentially to velocity, yet for Planck, the increase is linear to the frequency (which in a way is like velocity if you consider that the frequency increases 1:1 with velocity when doppler shifted).

I can't see the real connection between these two formulas. Is there a way to convert between them?

Thanks.
 
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Well you have to understand the Plancks fromula is for photons. Where as Newtons formula is for objects. Next part is that yes velocity is the most determining factor in Newtons law but Photon travel at the speed of light which is constant. It does not ever change even if its doppler shifted. when an a light wave is doppler shifted its frequency changes.

As far as the connection? You can connect the two some how to find the rest mass of a photon... I think...
Another connection is the Photoelectric affect. Where you can calculate the energy of the photon by adding the Kinetic energy of the Electron and its bond energy, which will be equal to E=hv.

Hope that makes sense,
Fox
 

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