The wavelength of `K_(alpha)` line in copper is `1.54 Å`. The ionisation energy of `K` electron in copper in Joule is

Explanation

To find the ionization energy of the K electron in copper given the wavelength of the K-alpha line, we can follow these steps:

### Step-by-Step Solution:

1. **Convert Wavelength to Meters:**
The wavelength of the K-alpha line is given as \(1.54 \, \text{Å}\). We need to convert this to meters:
\[
1.54 \, \text{Å} = 1.54 \times 10^{-10} \, \text{m}
...