A 100 watt bulb emits monochromatic light of wavelength 400 nm. Calculate the number of photons emitted per second by the bulb.

Explanation

To calculate the number of photons emitted per second by a 100 watt bulb emitting monochromatic light of wavelength 400 nm, we can follow these steps:

### Step 1: Understand the relationship between power, energy, and time
Power (P) is defined as the energy (E) emitted per unit time (t). The formula for power is:
\[ P = \frac{E}{t} \]
Since we want to find the number of photons emitted per second, we can express energy in terms of the number of photons.

### Step 2: Use the formula for energy of photons
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