Calculating wavelengths from given frequency range and the speed of light:
Wavelength corresponding to a frequency of [tex]4*10^{14}Hz[/tex]:
[tex]Wavelength =\frac{Speed of light}{Frequency}[/tex]
[tex]=\frac{2.998*10^{8}m/s} {4*10^{14}Hz } *\frac{10^{9}nm} {1 m}=749.5 nm[/tex]
Wavelength corresponding to a frequency of [tex]7.5*10^{14}Hz[/tex]:
[tex]Wavelength =\frac{Speed of light}{Frequency}[/tex]
[tex]=\frac{2.998*10^{8}m/s} {7.5*10^{14}Hz } *\frac{10^{9}nm} {1 m}=399.7 nm[/tex]
So the wavelength range will be 749.5 nm - 399.7 nm
This corresponds to the visible region wavelength range.
Hence the correct answer: C. visible light
