unscientific
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Homework Statement
Homework Equations
The Attempt at a Solution
Is my initial assumption wrong?
Relation between group velocity and phase velocity
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Is my initial assumption wrong?
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Science Advisor
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unscientific said:Homework Statement
Homework Equations
The Attempt at a Solution
Is my initial assumption wrong?
No, it's right.
unscientific
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rude man said:
But I seem to be missing out on a 1/vph term..
Science Advisor
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unscientific said:
You asked if you initial assumption was right. I did not check all your work. Will try later.
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You wrote dk/dw = (2pi/0)dn/dw.
However, k depends on more than w:
dk = ∂k/∂w dw + ∂k/∂n dn
So 1/vg = dk/dw = ∂k/∂w + ∂k/∂n dn/dw
= n/c + (w/c) dn/dw
Etc.
However, k depends on more than w:
dk = ∂k/∂w dw + ∂k/∂n dn
So 1/vg = dk/dw = ∂k/∂w + ∂k/∂n dn/dw
= n/c + (w/c) dn/dw
Etc.