Chapter 9, Problem 48R

To determine

The speed at which microwaves travel.

Answer to Problem 48R

The speed at which microwaves travel is $3\times {10}^8\text{m}/\text{s}$ .

Explanation of Solution

Given info:

Frequency of wave, $f=2,500,000,000\text{Hz}$

Wavelength of wave, $\lambda =12\text{cm}$

Formula used:

Wave frequency of a wave can be obtained by,

$\text{Wave}\text{speed}=\text{Wave}\text{frequency}\times \text{Wavelength}$

Calculation:

Substitute the given values in the above equation.

$\begin{array}{c}\text{Wave}\text{speed}=\left(2,500,000,000\text{Hz}\right)\left(2.5\text{cm}\right)\\ =\left(2,500,000,000\text{Hz}\right)\left(12\text{cm}\right)\left(\frac{1\text{m}}{100\text{cm}}\right)\\ =3\times {10}^8\text{m}/\text{s}\end{array}$

Conclusion:

Hence, the speed at which microwaves travel is $3\times {10}^8\text{m}/\text{s}$ .