Find the wave number of a photon having an energy of 2.072 eV.
Given :
Charge on electron `=1.6xx10^(-19)C`
Velocity of light air `=3xx10^(8)" m"//"s"`
Planck's constant `=6.63xx10^(-34)" J-s"`.

Explanation

To find the wave number of a photon with an energy of 2.072 eV, we will follow these steps:

### Step 1: Convert Energy from eV to Joules
The energy of the photon is given in electron volts (eV). We need to convert this energy into joules (J) using the conversion factor:
\[ 1 \text{ eV} = 1.6 \times 10^{-19} \text{ J} \]

So, the energy in joules is:
\[
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