Question

Violet light has a wavelength of 4.10X10-12m what is the frequency

Answer 1

The relation between frequency and wavelength is:

$\nu = \frac{c}{\lambda} = \frac{3\cdot 10^8\ m/s}{4.1\cdot 10^{-12}\ m} = \bf 7.32\cdot 10^{19}\ s^{-1}$