How many photons are emitted per second by a 5 m W laser source operating at 632.8nm?

Explanation

To find the number of photons emitted per second by a 5 mW laser source operating at a wavelength of 632.8 nm, we can follow these steps:

### Step 1: Understand the relationship between power, energy, and number of photons.
The energy of a single photon can be calculated using the formula:
\[ E = \frac{hc}{\lambda} \]
where:
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