Question

Violet light has a wavelength of 4.10 x 10^-12 m. What is the frequency?

Answer 1

Answer : The frequency of violet light is $7.32\times 10^{19}s^{-1}$

Explanation : Given,

Wavelength of violet light = $4.10\times 10^{-12}m$

Formula used :

$\nu=\frac{c}{\lambda}$

where,

$\nu$ = frequency of light

$\lambda$ = wavelength of light

c = speed of light = $3\times 10^8m/s$

Now put all the given values in the above formula, we get:

$\nu=\frac{3\times 10^8m/s}{4.10\times 10^{-12}m}$

$\nu=7.32\times 10^{19}s^{-1}$

Therefore, the frequency of violet light is $7.32\times 10^{19}s^{-1}$

Answer 2

Frequency = speed of light/wavelength 
speed of light = ~ 3 x 10^8 m/s.