Question

Sunburn is caused by ultraviolet light waves having a frequency of around 10^16 Hz. What is their wavelength if the speed of light is 3 x 10^8 m/s?
15 nm
69 cm
45 mm
30 nm

Answer 1

$Given:\\f=10^{16}Hz\\c=3\cdot 10^8\frac{m}{s} \\\\Find:\\\lambda =?\\\\Solution:\\\\\lambda = \frac{c}{f} \\\\\lambda= \frac{3\cdot 10^8\frac{m}{s}}{10^{16}Hz} =3\cdot 10^{-8}m = 30nm$