# Energy of an electron

ajith.mk91
Suppose we have 3 equipotential surfaces V1 V2 & V3(V1>V2>V3) and an electron residing in second surface and roaming freely with kinetic energy say K.E. Now if our K.E is greater than e(V1-V2) will the electron jump to the top surface with decreased kinetic energy? On the other hand will it jump to the lower state?If none of the above happens how will an electron jump to higher states if we provide external energy(as in the case of energy bands)?

Homework Helper
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hi ajith.mk91! welcome to pf!
Suppose we have 3 equipotential surfaces V1 V2 & V3(V1>V2>V3) and an electron residing in second surface and roaming freely with kinetic energy say K.E. Now if our K.E is greater than …

it can't have any KE …

compare it with a body orbiting the Earth at a particular radius …

to do so it must have a particular speed (and KE) …

it stays on that equipotential surface not because the potential is constant, but because its gradient exactly matches its KE

same for an electron in an electromagnetic field

ajith.mk91
Do you mean to say that both PE and KE are interrelated? If they are,which law governs their relation?
And secondly what is meant by KE of a hole in the valence band. Is it the KE of incoming electron?

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