What will be the frequency of photon of wavelength `1.215Å` travelling in vacuum?

Explanation

To find the frequency of a photon with a given wavelength, we can use the formula that relates the speed of light (C), frequency (ν), and wavelength (λ):

\[ C = ν \cdot λ \]

Where:
- \( C \) is the speed of light in vacuum (approximately \( 3 \times 10^8 \) meters per second).
- \( ν \) is the frequency in Hertz (Hz).
- \( λ \) is the wavelength in meters.
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