What is the frequency of $20 - \mathrm { mm }$ microwaves? $\left( c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } \right)$
A) $15 \mathrm { GHz }$
B) $100 \mathrm { MHz }$
C) $400 \mathrm { MHz }$
D) $73 \mathrm { GHz }$

Question

Quizplus · Accepted Answer

The frequency $f$ of a wave is given by the equation $f = \frac{c}{\lambda}$, where $c$ is the speed of light ($3.0 \times 10^8 \, \mathrm{m/s}$) and $\lambda$ is the wavelength. Given a $20 \, \mathrm{mm}$ ($20 \times 10^{-3} \, \mathrm{m}$) wavelength, $f = \frac{3.0 \times 10^8}{20 \times 10^{-3}} = 15 \times 10^9 \, \mathrm{Hz}$ or $15 \, \mathrm{GHz}$.

What Is the Frequency Of 20−mm20 - \mathrm { mm }20−mm

What Is the Frequency Of $20 - \mathrm { mm }$