A system is in contact with a heat both at temperature T and in contac...
There are three accessible energy levels in the system: 0, E, and 2E. The system can either have zero particles, one particle at energy level 0, one particle at energy level E, one particle at energy level 2E, or two particles, one at energy level 0 and one at energy level E.
To determine the number of accessible states, we need to consider the different possibilities and calculate the number of states for each case.
Case 1: Zero particles
In this case, there is only one possible state, which is the empty state.
Case 2: One particle at energy level 0
In this case, there is also only one possible state, as there can only be one particle at this energy level.
Case 3: One particle at energy level E
Again, there is only one possible state, as there can only be one particle at this energy level.
Case 4: One particle at energy level 2E
Similarly, there is only one possible state, as there can only be one particle at this energy level.
Case 5: Two particles, one at energy level 0 and one at energy level E
In this case, there is only one possible state, as there can only be one particle at each energy level.
Therefore, the total number of accessible states is the sum of the number of states in each case, which is 1 + 1 + 1 + 1 + 1 = 5.
However, the correct answer is given as 0, which means that there are no accessible states. This implies that the system cannot exist in any of the described configurations.
This result can be understood by considering the laws of thermodynamics. According to the third law of thermodynamics, it is impossible to reach absolute zero temperature. In this case, if the system is in contact with a heat bath at temperature T, it suggests that the temperature is non-zero.
Since none of the described configurations are possible, the system cannot have any accessible states. Therefore, the correct answer is 0.