Nexrad radar uses electromagnetic radiation of frequency of $2.7 \mathrm{GHz}$ to measure the speed of cloud systems. Radio waves from a transmitter are sent outward toward a cloud system, and the waves are reflected back toward the source. If the cloud system is moving, the reflected waves will be Doppler shifted. Suppose a Nexrad system observes clouds moving toward the transmitter at $21 \mathrm{~m} / \mathrm{s}$. What is the difference between the transmitted and received frequencies of the radar in this case?
A) $570 \mathrm{~Hz}$
B) $190 \mathrm{~Hz}$
C) $380 \mathrm{~Hz}$
D) $760 \mathrm{~Hz}$

Question

Quizplus · Accepted Answer

The Doppler shift formula for frequency is $\Delta f = \frac{2fv}{c}$, where $f$ is the original frequency, $v$ is the velocity of the object, and $c$ is the speed of light. Substituting the given values: $\Delta f = \frac{2 \times 2.7 \times 10^9 \times 21}{3 \times 10^8} = 380 \mathrm{~Hz}$.

Nexrad Radar Uses Electromagnetic Radiation of Frequency Of 2.7GHz2.7 \mathrm{GHz}2.7GHz To Measure the Speed of Cloud Systems

Nexrad Radar Uses Electromagnetic Radiation of Frequency Of $2.7 \mathrm{GHz}$ To Measure the Speed of Cloud Systems