Conditions for quantised or continuous energies

aurora14421
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Homework Statement



For a particle moving in a potential V(x), what are plausible forms of V(x) that give:

(i) entirely continuous,

(ii)entirely quantised

(iii) both continuous and quantised

energies of the particle? Sketch, with justification, the forms of V(x) for each of these 3 cases.


Homework Equations





The Attempt at a Solution



(i) when the particle is free (V(x) is zero), the particles energies are continuous.

(ii) When the particle is in an infinite potential well, the energies are quantised.

(iii) I have no idea about this one. Can anyone help?
 
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How about a square well whose sides have finite potential instead of infinite? Can you explain why that would work?
 
So it would have quantised energy inside the well (since it's confined) and continuous energies outside the well?
 
If you mean by 'in' that it has energy less than the wall energy, yes.
 
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