What is the Fermi energy of Liquid He3 at absolute zero?

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SUMMARY

The Fermi energy of liquid He^3 at absolute zero can be calculated using the formula ε_F = (ħ²/2m)(3π²N/V)^(2/3). In this discussion, the density of liquid He^3 is given as 0.081 g/cm³, which is used to derive the number density necessary for the calculation. The user initially misapplied the density, leading to incorrect units for energy. The correct approach involves using number density instead of mass density to obtain the correct units for ε_F.

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  • Understanding of Fermi energy and its significance in quantum mechanics
  • Familiarity with the properties of fermions, specifically He^3
  • Knowledge of basic thermodynamic equations related to Fermi temperature
  • Proficiency in unit conversions and dimensional analysis
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  • Research the concept of number density in quantum mechanics
  • Study the derivation of Fermi energy for different fermions
  • Learn about the implications of Fermi temperature in low-temperature physics
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Students and researchers in condensed matter physics, particularly those studying low-temperature phenomena and the properties of fermionic systems like liquid He^3.

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Homework Statement



The atom He^3 has spin 1/2 and is a fermion. The density of liquid He^3 is 0.081g/cm^3 near absolute zero. Calculate the Fermi energy \epsilon_F and the Fermi temperature T_F

Homework Equations



\epsilon_F = \frac{\hbar^2}{2m}(\frac{3 \pi^2 N}{V})^{2/3}

T_F = \frac{\epsilon_F}{k}

The Attempt at a Solution



In the problem I'm given the density is 0.081g/cm^3, which is my N/V. Assuming that m is the mass of He^3, then m = 5.008*10^{-24}g. I should then be able to do a straight forward plug-n-chug; however my units don't work out as I get:

\epsilon_F = \frac{\hbar^2}{1.0016*10^{-23}g}(3 \pi^2 0.081g cm^{-3})^{2/3}=1.99*10^{-50} kg^{5/3} m^2 s^{-2}

Clearly, this is not a unit of energy. What am I doing wrong?
 
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I need to use number density, rather than straight density. Which should take care of my problem.
 

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