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A beam of electromagnetic waves is bounced off the car
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∙ 12y ago
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A police radar gun measures the speed of a car by?
It measures the time it takes for the radar pulse to go from the radar gun to your vehicle and back. The pulse is fairly constant so the radar gun is getting updates and by comparing the updates to the time it can determine speed.
What is the tool use to measure speed?
An anemometer is used to measure wind speed. A Pitot Tube is used to infer speed in an aeroplane,. A speedometer in an ordinary car, and a microwave or laser radar in a Police car.
How do cobra radar detectors work and who uses them?
Cobra radar detectors are devices used to detect if the police are monitoring your car or checking your speed limit using a radar gun. This is used by motorist so they can fix their speed before getting pulled over.
What are speed guns?
A speed gun is a handheld Radar or Laser unit used by traffic police to check how fast a car is going.
What do police use to see the speed of a car?
radar waves.
Is police radar accurate when he is traveling toward you?
Yes. The radar calculating unit is reading more than one speed. It reads the patrol car speed from stationary objects (the ground, signs, etc.) and subtracts that speed from the speed at which your car and his car are coming together. If the patrol car is doing 38 and you are doing 55, the radar unit will read 38 from the ground and 93 from your car. It subtracts the 38 from the 93 and displays your speed as 55.
What is example of indirect measurement?
-thermometer -measuring the speed of the car "radar"
Can radar guns be used while vehicle is moving?
No, if you are moving 30 mph and another car is too, the radar would say the car is going 0 mph. depends on where you are... in some areas yes Thats the idea, radar guns are used to check a vehicles speed, if you mean can a radar gun be used from a moving vehicle then no, the gun must be stationary otherwise an inaccurate reading will result.
How does the frequency of a cars returning radar signal change if the car moves away from the radar source?
The frequency of the radar signal does not change. Be it a cop getting you speed, or a modern car with Brake assist (they use a radar signal to assist keeping a safe distance) it's all timing, how long from the radar source to return to source. If a police car is still, and you are moving away, the increase in return of signal time tells the computer in the officer's car your speed. Even if you are going toward each other, the computer knows the speed of the officer's car and again, signal return time factored in with speed of cop car the computer can give an instant, real-time speed.
What are the benefits of having a radar detector?
Having a radar detector will alert you when a Police Car with its speed radar is near. The Radar Detectors will produce an audible signal alerting you of this, and will do so far in advance of when you are able to see the Police Car.
What is Doppler Radar?
Doppler Radar uses the Doppler effect to determine speed toward or away from the Radar. When a Radar return has a higher frequency than the transmitted pulse, the object is coming closer, and the *difference in frequency determines speed. Lower frequency- object is moving away. This is used by police, and for weather Radar to help detect not only speed but to detect patterns characteristic of tornadoes. Also used for other applications not just military. You are your own Doppler system using audible frequencies. You can tell when a car, plane, or train is approaching vs moving away.
How radiation helps the police?
um radar guns emit radiation ........they use the radar guns to find the speed of a speeding car.
