What is the Fermi energy of metallic potassium at 0K?

AI Thread Summary
The discussion revolves around calculating the Fermi energy of metallic potassium at absolute zero (0K). The relevant equation for Fermi energy is provided, which incorporates the number of atoms per cubic meter and their contribution to the free electron gas. A participant initially confuses the variable V with voltage but is clarified that V represents volume in the context of the equation. The key takeaway is that the calculation does not require the explicit value of V, as it is used in the form of N/V, the number of electrons per unit volume. This understanding resolves the confusion and allows for the correct application of the formula.
joel.martens
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Homework Statement


We must calculate the Fermi energy of metallic potassium at 0K. We have aleady found the number of atoms per m cubed, we are told that each atom contributes one electron to the free electron gas.

Homework Equations



Fermi energy = ((hbar^2)/2m)(((3Pi^2)N)/V)^3/2

The Attempt at a Solution


My problem is that i don't know what V is supposed to be. I thought that since each K gives one electron to become K+, V might be +e, but that gave a nonsensical answer.
 
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Need more info? better explanation?
Pls help!
 
You don't need to know V, since the formula involves V only in the form N/V, i.e. the number of electrons per unit volume.
 
ooooooooooooooh, V for volume. Thankyou, i was stuck on thinking voltages.
 
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