The energy of a photon of sodium light `( lamda = 589 nm)` equal to the band gap of a semiconducing material . Find the minimum energy E required to create a hole -electron pair.

Explanation

To solve the problem of finding the minimum energy \( E \) required to create a hole-electron pair in a semiconductor material, given that the energy of a photon of sodium light (with a wavelength of \( \lambda = 589 \, \text{nm} \)) is equal to the band gap energy of the semiconductor, we can follow these steps:

### Step 1: Understand the relationship between energy and wavelength
The energy of a photon can be calculated using the formula:
\[ E = \frac{hc}{\lambda} \]
where:
...