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LarryS

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As always, thanks in advance.

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- Thread starter LarryS
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- #1

LarryS

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As always, thanks in advance.

- #2

gneill

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Before the electron even enters the region of the magnetic field it already possesses angular momentum about the future center of the circular arc.

- #3

A.T.

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As @gneill notes: It has angular momentum even when it's moving in a straight line, around any point not on that line.During the “turning” of the electron (a finite time interval), does it temporarily possesses classical orbital angular momentum?

What exactly do you mean by "classical orbital angular momentum"? There is some abiguity:

https://en.wikipedia.org/wiki/Orbital_angular_momentum

- #4

Dale

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Yes, except that it is probably much less temporary than you might assume.During the “turning” of the electron (a finite time interval), does it temporarily possesses classical orbital angular momentum?

- #5

QLogic

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Not exactly, although the distinction is a pedantic one to a certain degree in such a situation. It is still the case that one might measure the electron in a basis not commuting with Angular Momentum. Only if we have an experimental set up which can measure angular momentum can we then say (assuming the wave function is reasonably "tight" about a classical path) that it has orbital angular momentum.Before the electron even enters the region of the magnetic field it already possesses angular momentum about the future center of the circular arc

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- #6

gneill

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Keep in mind that this problem is posed in a "Classical Physics" domain.Not exactly, although the distinction is a pedantic one to a certain degree in such a situation. It is still the case that one might measure the electron in a basis not commuting with Angular Momentum. Only if we have an experimental set up which can measure angular momentum can we then say (assuming the wave function is reasonably "tight" about a classical path) that it has orbital angular momentum.

- #7

QLogic

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Well if the electron is treated as a classical object then it definitely has orbital angular momentum. I thought usage of "Keep in mind that this problem is posed in a "Classical Physics" domain.

- #8

Dale

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I guess you missed the word “classical”. He is talking about a classical point charge, not an actual electron.one might measure the electron in a basis not commuting with Angular Momentum

- #9

gneill

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No harm, no foul. I frequently misinterpret intended situations until I stand back and look at the context.Well if the electron is treated as a classical object then it definitely has orbital angular momentum. I thought usage of "temporarily possesses classicalorbital angular momentum" suggested the electron was being treated quantum mechanically.

- #10

LarryS

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Thanks, I forgot just how general the definition of classical angular momentum was.I'm not sure if there's any technical distinction between regular "angular momentum" and "orbital angular momentum", save that one is associated with an orbiting body.

Before the electron even enters the region of the magnetic field it already possesses angular momentum about the future center of the circular arc.

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