Answer:
Wavelength of this beam of light: [tex]\rm 4.39\times 10^{-7}\; m[/tex].
Explanation:
The speed of light in vacuum is approximately [tex]\rm 2.998\times 10^{8}\;m \cdot s^{-1}[/tex].
Light behaves like a wave. The wavelength of a wave is equal to the distance that it travels (in the given medium) in each period of oscillation.
On the other hand, the frequency of a wave is the number of periods in unit time. [tex]1\rm \; Hz[/tex] means one oscillation per second. The frequency of this particular wave is [tex]\rm 6.83\times 10^{14}\; Hz[/tex]. In other words, there are [tex]6.83\times 10^{14}[/tex] oscillations in each second.
The period of oscillation will be equal to
[tex]\displaystyle t = \frac{1}{f} = \frac{1}{\rm 6.83\times 10^{14}\; s^{-1}}[/tex].
In that period of time, a beam of light in vacuum would have traveled Â
[tex]\displaystyle \rm 2.998\times 10^{8}\; m\cdot s^{-1} \times \frac{1}{\rm 6.83\times 10^{14}\; s^{-1}} = 4.39\times 10^{-7}\; m[/tex].
In other words, if this beam of light of frequency [tex]\rm 6.83\times 10^{14}\; Hz[/tex] is in vacuum, its wavelength will be equal to [tex]\rm 4.39\times 10^{-7}\; m[/tex].