Each colour has different wavelengths....
For example: In VIBGYOR
It is in the order of increasing wavelength i.e Compared to red violet is having the shorter wavelength.....
The frequency and wavelength are related by the equation:
In vaccum: frequency= c/wavelength
where
c is the velocity of light in free space
Whereas in any medium,
frequency= Velocity of light in that medium/wavelength
So, it is clear from the formula that the wavelength and frequency are inversely proportional to each other....
As the wavelength changes with colour the frequency also changes according to that..............
If the frequency is high, the wavelength will be low and viceversa....