Question

A beam of light has a wavelength of 4.5 x10^-7 meter in a vacuum. the frequency of this light is

Answer 1

The basic relationship between frequency and wavelength for light (which is an electromagnetic wave) is

`c= f \lambda`
where c is the speed of light, f the frequency and
`\lambda` the wavelength of the wave.
Using
`\lambda=4.5 \cdot 10^(-7) m` and
`c=3 \cdot 10^8 m/s`, we can find the value of the frequency:

`f= (c)/(\lambda)= (3 \cdot 10^8 m/s)/(4.5 \cdot 10^(-7) m)=6.7 \cdot 10^(14) Hz`