Group and phase velocity of a wave

AI Thread Summary
The discussion centers on the relationship between de Broglie wavelength, particle mass, and velocity. It clarifies that the velocity calculated from the de Broglie wavelength formula (λ = h/mv) is typically the phase velocity, not the group velocity. The group and phase velocities can be the same when a particle has a definite momentum, but differ in the case of a wave packet with indeterminate momentum. Additionally, for particles like electrons moving close to the speed of light, the distinction between phase and group velocities remains relevant. Understanding these concepts is crucial for analyzing wave-particle duality in quantum mechanics.
Sharlom
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If i am given the de broglie wavelength
Of any particle then its sure that i can find the velocity of tat particle if its mass is given.
λ= h/mv
But the velocity which i found is the group velocity or phase velocity?If it's not the group velocity
How can i find it?
 
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If the particle has a definite momentum, it has a definite velocity, so the group velocity is the same as the phase velocity in that case. They are different if you have a "wave packet", which is a state of indeterminate momentum.
 
If the particle electron is moving nearly at speed of light then also
Is phase and grp velocities the same?
 

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