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 of calculating the threshold frequency \( v_0 \) and the work function \( W_0 \) of the metal when electrons are emitted with zero velocity from a metal surface exposed to radiation of wavelength \( 6800 \) Å, we will follow these steps:

### Step 1: Convert Wavelength to Meters
The given wavelength is in angstroms, and we need to convert it to meters for our calculations.
\[ \text{Wavelength} (\lambda) = 6800 \, \text{Å} = 6800 \times 10^{-10} \, \text{m} \]

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