Question
Download Solution PDFThe degeneracy of the state having energy \(\rm\frac{27 h^2}{8mL^2}\) for a particle in a 3-D cubic box of length L is
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
In a three-dimensional cubic box, the energy of a particle is given by the equation:
\(E = h²(n₁² + n₂² + n₃²) / 8mL²\)
where: E is the energy, h is Planck's constant, n₁, n₂, and n₃ are the quantum numbers associated with the particle (they can be any positive integer), m is the mass of the particle, and L is the length of the box.
Explanation:
You're given that the energy E is 27h2/ 8mL2 . Setting this equal to the energy equation, we get:
\(27h² / 8mL² = h²(n₁² + n₂² + n₃²) / 8mL²\)
Solving for n₁² + n₂² + n₃², we find that it equals 27. This means that the sum of the squares of the three quantum numbers equals 27.
The possible sets of quantum numbers (n1, n2, n3) that satisfy this equation are (3, 3, 3), (1, 1, 5), (1, 5, 1), and (5, 1, 1). Each set of quantum numbers corresponds to a different state of the particle, so there are four states that have this energy.
Conclusion:-
Therefore, the degeneracy of the state with energy \(27h² / 8mL²\) is 4
Last updated on Jun 5, 2025
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