Light of wavelength 2000 Å falls on a metallic surface whose work function is 4.21 eV. Calculate the stopping potential

Explanation

To solve the problem of calculating the stopping potential when light of wavelength 2000 Å falls on a metallic surface with a work function of 4.21 eV, we will follow these steps:

### Step 1: Convert the wavelength to meters
The wavelength given is in angstroms. We need to convert this to meters for our calculations.
\[ \text{Wavelength} (\lambda) = 2000 \, \text{Å} = 2000 \times 10^{-10} \, \text{m} = 2 \times 10^{-7} \, \text{m} \]

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