Have you any idea about the electron speed at 0K when the electron is free?
In the free electron model of solids, I belive that the fermi velocity is approx 10^6 m/s
Of course, this depends on the electron density in the solid (and is true, independent of the model).
A truly free electron, however, can have any velocity (v<c) you give it. And whose temperature are you (pang) talking about?
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