The frequency of light wave is 0.6*10^15 Hz.
The relation between the speed of light, frequency, and wavelength is given as
c=λν
Plugging the values in the above equation
3*10^8=5*10^(-7)*ν
ν=0.6*10^15 Hz.
Therefore the frequency of the light wave is 0.6*10^15 Hz.