Four identical fermion particles are to be distributed in two energy l...
Solution:
Given: Four identical fermion particles, two energy levels E1 and E2; E1 is 5-fold degenerate and E2 is 6-fold degenerate.
To find: The energy corresponding to the distribution having the maximum number of arrangements.
Arrangement of 4 identical fermion particles in two energy levels:
- E1E1E1E1
- E1E1E1E2
- E1E1E2E2
- E1E2E2E2
- E2E2E2E2
Calculation of the number of arrangements:
- For the first arrangement, all particles are in the E1 energy level. The number of arrangements for this is 1.
- For the second arrangement, 3 particles are in the E1 energy level and 1 particle is in the E2 energy level. The number of arrangements for this is 4C1 = 4.
- For the third arrangement, 2 particles are in the E1 energy level and 2 particles are in the E2 energy level. The number of arrangements for this is 4C2 = 6.
- For the fourth arrangement, 1 particle is in the E1 energy level and 3 particles are in the E2 energy level. The number of arrangements for this is 4C1 = 4.
- For the fifth arrangement, all particles are in the E2 energy level. The number of arrangements for this is 1.
Total number of arrangements = 1 + 4 + 6 + 4 + 1 = 16
Calculation of the energy corresponding to the distribution having the maximum number of arrangements:
- For the third arrangement, 2 particles are in the E1 energy level and 2 particles are in the E2 energy level. The energy corresponding to this distribution is 2(E1 + E2).
- For the first arrangement, all particles are in the E1 energy level. The energy corresponding to this distribution is E1.
- For the second arrangement, 3 particles are in the E1 energy level and 1 particle is in the E2 energy level. The energy corresponding to this distribution is 3E1 + E2.
- For the fourth arrangement, 1 particle is in the E1 energy level and 3 particles are in the E2 energy level. The energy corresponding to this distribution is E1 + 3E2.
- For the fifth arrangement, all particles are in the E2 energy level. The energy corresponding to this distribution is E2.
Therefore, the energy corresponding to the distribution having the maximum number of arrangements is 2(E1 + E2) (corresponding to the third arrangement).