How many photons of light having a wavelength of `4000Å` are necessary to provide 1J of energy ? `(h= 6.63 xx 10^(-34)J.s, c=3 xx 10^(8)m//s)`

Explanation

To solve the problem of how many photons of light with a wavelength of 4000 Å (angstroms) are necessary to provide 1 Joule of energy, we can follow these steps:

### Step 1: Convert Wavelength to Meters
The wavelength is given in angstroms, and we need to convert it to meters for our calculations.

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