What is the number of photons of light with wavelength 4000 pm which provide 1 Joule of energy ?

Explanation

To solve the problem of finding the number of photons of light with a wavelength of 4000 picometers that provide 1 Joule of energy, we can follow these steps:

### Step 1: Convert Wavelength to Meters
The given wavelength is 4000 picometers (pm). We need to convert this into meters for our calculations.

\[ \text{Wavelength} (\lambda) = 4000 \, \text{pm} = 4000 \times 10^{-12} \, \text{m} = 4 \times 10^{-9} \, \text{m} \]
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