Question

The radar gun measures the frequency of the radar pulse echoing off your car. By what percentage is the measured frequency different from the original frequency? (Enter a positive number for a frequency increase, negative for a decrease. Just enter a number, without a percent sign.)

Answer 1

Question: A. The state highway patrol radar guns use a frequency of 9.15 GHz. If you're approaching a speed trap driving 30.1 m/s, what frequency shift will your FuzzFoiler 2000 radar detector see?

B. The radar gun measures the frequency of the radar pulse echoing off your car. By what percentage is the measured frequency different from the original frequency? (Enter a positive number for a frequency increase, negative for a decrease. Just enter a number, without a percent sign.)?

Answer:

The frequency change percentage is 9.94%

Explanation:

The frequency shift can be calculated as follows.

$F= \frac{V+V_{0}}{V+V_{s}}$

   = $9.05GHz\times\frac{343m/s+0}{343m/s+(-31.3m/s)}$

   =9.95 GHz

So the frequency change seen by the detector is 9.95 - 9.05

% difference$= \frac{0.9}{9.05} \times100$

                    = 9.94%