2006-12-06 08:59:58 · 5 answers · asked by tonysensation67 1 in Cars & Transportation ➔ Safety
A radar gun transmits a fairly wide beam, so if many cars are nearby in the direction the gun is pointing, the beam will illuminate them all. The Doppler effect causes each radar echo to be shifted upward in frequency, based on how fast that car is approaching the radar unit. So inside the unit, it's possible to detect all of the various returned frequencies, and determine all the different speeds with which cars are approaching. From that, the system can just pick the highest speed number, and display only that number.
2006-12-06 09:13:57 · answer #1 · answered by Grouchy Dude 4 · 0⤊ 0⤋
It doesn't. The cop just sees who the fastest one is, and knows he was going at least as fast as the radar display indicated.
2006-12-06 10:23:15 · answer #2 · answered by Nomadd 7 · 0⤊ 0⤋
Used to be by visual acquisiton. But I haven't run radar in a very long time. I think thery've got lasers now.
2006-12-06 09:08:58 · answer #3 · answered by Anonymous · 0⤊ 0⤋
the cops point the radar gun at your license plate (very reflective) the rays are reflected back to the gun... since they are aiming at a small location it's fairly error proof.... this is also why the state makes you replace your plate after a certain amount of years even if the plates in good condition... they want to be sure the rays are reflected back to them.
2006-12-07 00:38:59 · answer #4 · answered by streetrodmaniac 3 · 0⤊ 1⤋
They point it directly at the car.
2006-12-06 09:09:08 · answer #5 · answered by James Dean 5 · 0⤊ 0⤋