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What is the ground-state energy of ten non-interacting spin-1/2 fermions of mass m, in a one-dimensional box of length L?

B. What is the Fermi energy?

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Final answer:

The ground-state energy of ten non-interacting spin-1/2 fermions in a one-dimensional box of length L can be calculated using a formula. The Fermi energy can then be determined by dividing the total ground-state energy by the number of fermions.

Step-by-step explanation:

The ground-state energy of ten non-interacting spin-1/2 fermions in a one-dimensional box of length L can be calculated using the formula:

E = (n^2 * h^2)/(8mL^2)

where n is the principal quantum number, h is Planck's constant, m is the mass of the fermions, and L is the length of the box.

Since there are 10 fermions, we need to find the sum of the ground-state energies for each fermion:

  • For a spin-1/2 fermion, there are two possible states: spin-up and spin-down.
  • We can calculate the ground-state energy for one fermion by taking the sum of the energies for both spin states.

Once we have the total ground-state energy, we can calculate the Fermi energy by dividing it by the number of fermions.

User Hoetz
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Final answer:

The ground-state energy of ten non-interacting spin-1/2 fermions in a one-dimensional box is the sum of the energies of the first five filled levels. The Fermi energy is the energy of the highest filled level at absolute zero. The calculations are based on the quantized energy levels of particles in a one-dimensional potential well.

Step-by-step explanation:

The question concerns the ground-state energy and Fermi energy of ten non-interacting spin-1/2 fermions in a one-dimensional box, a topic within the realm of quantum mechanics. In a one-dimensional potential well or box, the energy levels of a particle are quantized. For non-interacting spin-1/2 fermions, such as electrons, each energy level can be occupied by two particles due to their two possible spin states, following the Pauli exclusion principle.

The ground-state energy is the sum of the energies of the lowest states that all the fermions occupy. For the ten fermions to be in the lowest possible energy states, the first five levels would be filled, since each level can hold two fermions. Calculating these energies requires using the formula for the energy levels in a one-dimensional box, E_n = (n^2 π^2 ĭ^2)/(2mL^2), where ĭ is the reduced Planck constant, m is the particle mass, n is the principal quantum number, and L is the length of the box. To find the total ground-state energy, you sum the energies of each occupied level.

The Fermi energy is the energy of the highest occupied single-particle state at absolute zero. This corresponds to the energy of the highest filled level when all the lower energy states are fully occupied.

User DragonLord
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