An electron wave-packet moves at the speed of
(A) the electron waves that form it.
(B) an electron with the same momentum.
(C) light.
(D) an electron with half its momentum.
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What this question is about
An electron wave-packet moves at the speed of
(A) the electron waves that form it.
No. --- That only happens when all
of the waves travel at the same speed.
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An electron wave-packet moves at the speed of
(B) an electron with the same momentum.
Yes.
That was deBroglie's great triumph.
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An electron wave-packet moves at the speed of
(C) light.
No.
It travels much slower than that.
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An electron wave-packet moves at the speed of
(D) an electron with half its momentum.
No. --- The wave crests travel at that speed
but not the packet.
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