The second is defined as the time it takes

The second is defined as the time it takes for 9,192,631,770 wavelengths of a certain transition of the cesium-133 atom to pass a fixed point. What is the frequency of this electromagnetic radiation? What is the wavelength?


The frequency of this electromagnetic radiation is already given to us in the question. It is simply 9,192,631,770 per second.

To calculate the wavelength, we will use this formula:


(Where \lambda is the wavelength, c is the speed of light, and v is frequency)


Speed of light = 2.99792458\times 10^8\dfrac{m}{s}


Substituting the values we know and solving for \lambda gives us:

\lambda=\dfrac{2.99792458\times 10^8\dfrac{m}{s}}{9,192,631,770/s}


\lambda=0.0326122557 m


This question can be found in General Chemistry, 9th edition, chapter 7, question 7.42


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