Light of wavelength 221 nm falls on a totally reflecting plane mirror at an angle `30^@` with the mirror. If `10^20` photons are striking the mirror per second , then what will the force exerted on the mirror ?

Explanation

To solve the problem of finding the force exerted on a totally reflecting plane mirror by photons striking it, we can follow these steps:

### Step 1: Understand the Problem
We are given:
- Wavelength of light, \( \lambda = 221 \, \text{nm} = 221 \times 10^{-9} \, \text{m} \)
- Angle of incidence, \( \theta = 30^\circ \)
- Number of photons striking the mirror per second, \( n = 10^{20} \, \text{photons/s} \)

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