Question

Calculate the frequency of (a) radio waves which have a wavelength of $3\times {10}^7\stackrel{\circ }{A}$, and (b) violet radiations having a wavelength of $3\times {10}^{-11}cm$.

Answer 1

Given,

$Wavelength=3\times {10}^{7}A$

The wavelength of the violet radiation is $3\times {10}^{-11}$

Since the velocity of the light is equal to he velocity of the light is:

$3\times {10}^8$

a) The frequency of the radio wave:

$f=\frac{v}{\lambda }=\frac{3\times {10}^8}{3\times {10}^7\times {10}^{-10}}={10}^{11}Hz.$

b) The frequency of the violet radiation is:

$f=\frac{v}{\lambda }=\frac{3\times {10}^8}{3\times {10}^{-13}}={10}^{21}Hz.$