Question

The wavelength of the green laser of the light effect device is 531 nm.

What is the frequency of such light?

Answer 1

$λ = 531 \;nm = 531 \times 10^{-9} \;m \\ f=\frac{c}{λ}$

Light velocity $c = 3 \times 10^8 \;m/s$

$f = \frac{3 \times 10^8}{531 \times 10^{-9}} = 5.65 \times 10^{14}\;Hz$

Answer: $5.65 \times 10^{14}\;Hz$