Why Don't Electrons Absorb/Radiate Energy in Standard Orbit?

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Electrons in standard orbits do not absorb or radiate energy because they maintain constant potential and kinetic energy, resulting in stable momentum and wavelength. Absorption of energy would require a transition to a higher energy state, altering the electron's energy levels. In a circular Bohr orbit, the electron's wavelength aligns perfectly along its path, leading to constructive interference and preventing electromagnetic radiation. The absence of changes in electric and magnetic fields means there is no mechanism to initiate radiation. Thus, electrons in stable orbits remain in a state of energy equilibrium without emitting energy.
Naren Balaji
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when electrons are in their standard orbits , why is it that they don't absorb or radiate energy ??
 
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Please start by reading the FAQ sub-forum in the General Physics forum.

https://www.physicsforums.com/forumdisplay.php?f=209

Zz.
 
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An electron's "standard orbit" is a non-changing situation, so the electron has constant Potential Energy, and constant Kinetic Energy (hence constant momentum and constant wavelength).
1) If an electron DID absorb Energy (from a photon, for example), its total Energy would be changed (PE increases toward zero, and KE decreases ½ as far toward zero), which would be called a "transition" from initial state (orbit n1) to higher final state (orbit n2).

2) If you were asking why the electron doesn't radiate during its "circular Bohr orbit" (which has centripetal acceleration), the answer is that the electron's wavelength "fits" along its path so that it reinforces itself (constructive interference). Because there is no change in the Electric field, and no change in the Magnetic field, there is nothing to start EM radiation: so no Energy is emitted.
... it is the changing E-field and changing B-field, which become EM radiation from an accelerated charge ... the radiation is NOT deducible from Energy conservation
contrary to Zz's wording in the FAQ post ... it should be obvious that you can't derive a pair of vector fields {E(r), B(r)} from a single scalar equation.
 
It may be shown from the equations of electromagnetism, by James Clerk Maxwell in the 1860’s, that the speed of light in the vacuum of free space is related to electric permittivity (ϵ) and magnetic permeability (μ) by the equation: c=1/√( μ ϵ ) . This value is a constant for the vacuum of free space and is independent of the motion of the observer. It was this fact, in part, that led Albert Einstein to Special Relativity.
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