Question

The wavelength of light visible to the human
eye is on the order of 5 × 10−7 m.
Find the frequency of the lightwave if the
speed of light in air is 2.99792 × 108 m/s.
Answer in units of s−1.

Answer 1

The frequency of the electromagnetic wave

$$f=\frac{c}{\lambda}$$ $$=\frac{2.99792\times 10^8\:\rm m/s}{5\times 10^{-7}\:\rm m}=6\times 10^{14} \:\rm s^{-1}.$$