Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength ` 6800` Å . Calculate threshold frequency `( v_0)` and work function `(W_0)` of the metal.

Explanation

To solve the problem, we need to calculate the threshold frequency (\(v_0\)) and the work function (\(W_0\)) of the metal when it is exposed to radiation of wavelength \(6800 \, \text{Å}\) (angstroms).

### Step 1: Convert Wavelength to Meters
First, we need to convert the wavelength from angstroms to meters.

\[ 1 \, \text{Å} = 10^{-10} \, \text{m} \]
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