Answer:
[tex]1.5\cdot 10^{15}Hz[/tex]
Explanation:
The relationship between wavelength and frequency is given by:
[tex]c=f \lambda[/tex]
where
[tex]c=3\cdot 10^8 m/s[/tex] is the speed of light
f is the frequency
[tex]\lambda[/tex] is the wavelength
In this problem, we know the wavelength:
[tex]\lambda=2.0\cdot 10^{-7} m[/tex]
So we can re-arrange the formula above to find the frequency:
[tex]f=\frac{c}{\lambda}=\frac{3.0\cdot 10^8 m/s}{2.0\cdot 10^{-7} m}=1.5\cdot 10^{15}Hz[/tex]
