Answer: The correct answer is [tex]f=75\times 10^{13}[/tex] Hz.
Explanation:
The expression of the wavelength in terms of the frequency is as follows;
[tex]\lambda =\frac{c}{f}[/tex]
Here, c is the speed of the light, f is the frequency of the wave and [tex]\lambda[/tex] is the wavelength of the wave.
It is given in the problem that a visible violet light emits light with a wavelength of 4.00 × 10-7 m.
Calculate the frequency of the violet light by rearranging the above expression.
[tex]f=\frac{c}{\lambda }[/tex]
Put [tex]c=3\times 10^{8} m/s[/tex] and [tex]{\lambda }=4\times 10^{-7}[/tex].
[tex]f=\frac{3\times 10^{8}}{4\times 10^{-7}}[/tex]
[tex]f=75\times 10^{13} Hz[/tex]
Therefore, the frequency of the violet light is [tex]f=75\times 10^{13} Hz[/tex].
