A population inversion for two energy levels is often described by assigning a negative Kelvin temperature to the system. What negative temperature would describe a system in which population of the upper energy level exceeds that of the lower by `10%` and the energy difference between the two levels is 2.2 eV?

Explanation

To solve the problem of determining the negative temperature that describes a system with a population inversion, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Population Inversion**:
We know that the population of the upper energy level (n_x) exceeds that of the lower energy level (n_0) by 10%. This means:
\[
n_x = n_0 + 0.1 n_0 = 1.1 n_0
...