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Never get a ticket again!

  1. Dec 25, 2004 #1

    I was learning about radar in my physics class; I did some research and found out that there is a coating that can go over my license plate which will not give the officer an accurate reading of my speed. Does anyone know about this?

    I have to wait a few more days to find that particular site again.
  2. jcsd
  3. Dec 25, 2004 #2


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    It works best when you drive the speed limit, though.
  4. Dec 25, 2004 #3
    I do not agree with the limit.
  5. Dec 25, 2004 #4
    That would probably work as well as stating that the signs don't have units on them as they say speed limit 35.... instead of speed limit 35 mph, or trying to say that you weren't moving, the world was moving around you and you were holding still.
  6. Dec 25, 2004 #5
    fundamentally, i do not see the hazard in moving 85 mph relative to a stationary observer..hehe...versus 65mph
  7. Dec 25, 2004 #6
    watch some crash videos they might scare you a bit, although I don't mind doing a little over a hundred in a 40 mph I only have a saturn though, so much faster than that would require more road.
  8. Dec 25, 2004 #7
    I've watched the videos. I have been through defensive driving 4 times. Right, I agree. Those 40mph zones are ridiculous. As if going 40 vs 50 would make a difference. I will research that license plate coating. Or move to Germany.
  9. Dec 25, 2004 #8
  10. Dec 25, 2004 #9
    hard to believe this
    maybe correlation rather than causation
  11. Dec 25, 2004 #10
    Car-insurance telematics

    Excessive speed exponentially increases stopping distance and crash severity. Soon, a traffic ticket may be the least of your speeding worries, as insurance companies are gearing up to remotely monitor individual driving habits and to price unsafe drivers out of the market for car insurance.

    • According to a recent New York Times article, Acme Rent-a-Car in New Haven, CT fines its customers $150 each time they drive faster than 80 miles and hour for over two minutes. One hapless customer got nailed for $450. Sure, he shouldn't have been speeding, especially in a car that didn't belong to him. Maybe he deserved to pay the fine, but here's the problem: this kind of monitoring will be irresistibly attractive to car insurance companies. It's not hard to imagine that carriers will begin to offer a rate discount to people who agree to let their insurance companies access their cars’ telematics systems. Anyone who doesn't want to submit to telematics monitoring will be out of luck, because rates without the telematics discount will be simply unaffordable.
    Last edited by a moderator: Apr 21, 2017
  12. Dec 25, 2004 #11


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    I don't find it hard to believe at all -- but I think following distance is a more important factor. I see so many people blazing down the express ways with following distances that are barely appropriate for a 25 MPH zone. :frown:
  13. Dec 25, 2004 #12

    Ivan Seeking

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    My first impression is this this can't be done; not with a simple coating. There have been a host of bogus RADAR-proofing schemes, none of which worked. I am guessing that this "technology" claims to scatter the signal to create multiple returns that confuse the receiver. If so, this is an old scam with a new face.

    Maybe you can buy a stealth car...

    Oh yes, as someone who has spend many hours driving at high speeds, I have one piece of advice: Slow down. Most of my many close calls were only survived because by chance I had a fraction of a second in my favor.
    Last edited: Dec 25, 2004
  14. Dec 25, 2004 #13
    Whoever's selling the coating must be fans of P.T. Barnum.

    About the only thing I know that really 'defeats' radar is military stealth technology (building/painting the entire craft out of materials that absorb/scatter the incoming radar.) Even with this type of technology, these planes aren't completely invisible to radar, but since they're generally much farther away from the radar source than you would be from smokey the bear with his radar gun, they do the job quite well.

    I also don't find the figures on fatalities hard to believe. Increase your speed from 60 to 80 mph and you've nearly doubled your kinetic energy (a factor of 16/9.) Also, above a certain impact force, some of the car's safety features like crumple zones simply don't work anymore, making it more deadly than a simple increase in kinetic energy would indicate.
  15. Dec 26, 2004 #14
    The idea was too good to be true..*sniff*...guess I better slow down. I suppose that because I have been fortunate enough to not be in a crash, I do not recognize the danger of breaking the limit.

    But I still cannot believe that someone has not come up with an effective means of blocking radar. I had some ideas. If the radar is just perpendicular electric and magnetic fields propogating through space, why not have a different medium (other than air) surrounding your car to slow down the rate of propogation. I'm young. Let me dream. Or have an electric field surrounding my car. I don't think that will affect the incoming radar though....
  16. Dec 26, 2004 #15
    I heard that in some states or areas when the raised the speed limit from 65 to 75 accidents actually decreased. Their reasoning was that people felt safe at 65mph and thus were more careless and less attentive. At 75mph on the other hand, people felt like they should be more careful. Any truth to this?
  17. Dec 26, 2004 #16
    Saying good-bye to police radar

    Says that site:

    • The objective of the "Stealth Car Project" is to reduce the Radar Cross Section (RCS) of a vehicle. This reduction of RCS will reduce the range at which the vehicle is detectable by police radar or make it invisible altogether.

    I have been clocked multiple times on my bicycle by both automatic and manual police radar (the cops yell, "16 miles an hour!" with grins on their faces). I would think a bicyclist might have a pretty small radar cross section since a bicyclist is much smaller than a car. Getting even smaller, there is also a rumor that baseballs thrown in the direction of automatic police radar guns will produce accurate speed readouts. I wonder if a golf ball might also register.

    Since radar is unreliable (in 1999, a Eugene, Oregon cop pulled me over because he had clocked me at 45 and then 30 in a 30 MPH zone; I had been going 30 the whole time and he said to that that I must have been going 45 and "hit your brakes when you saw me"; what is the false-reading rate with radar - 10%, 20%, 30%?), I imagine it may soon be replaced wholesale by GPS-driven telematics. If that eventually happens, a stealth car might function as little more than an homage to the past.
    Last edited: Dec 26, 2004
  18. Dec 26, 2004 #17
    The body count of the 55 MPH speed limit?

    This is a similar study that found that 65 vs. 55 MPH increased freeway deaths but overall reduced deaths when the novel tactic of including non-freeway traffic deaths was included. (In the full text of the study, the authors reasoned in part that the 55 MPH speed limit discouraged drivers from hopping on the freeway where driving is, despite the higher speeds involved, overall safer than on any other type of road.):

    • Accid Anal Prev. 1994 Feb;26(1):49-62.
      Did the 65 mph speed limit save lives?
      Lave C, Elias P.

      Department of Economics, University of California, Irvine 92717.

      In 1987, most states raised the speed limit from 55 to 65 mph on portions of their rural interstate highways. There was intense debate about the increase, and numerous evaluations were conducted afterwards. These evaluations share a common problem: they only measure the local effects of the change. But the change must be judged by its system-wide effects. In particular, the new 65 mph limit allowed the state highway patrols to shift their resources from speed enforcement on the interstates to other safety activities and other highways--a shift many highway patrol chiefs had argued for. If the chiefs were correct, the new allocation of patrol resources should lead to a reduction in statewide fatality rates. Similarly, the chance to drive faster on the interstates should attract drivers away from other, more dangerous roads, again generating system-wide consequences. This study measures these changes and obtains surprising results. We find that the 65 mph limit reduced statewide fatality rates by 3.4% to 5.1%, holding constant the effects of long-term trend, driving exposure, seat belt laws, and economic factors.

      PMID: 8110357
  19. Dec 26, 2004 #18


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    The only such coating that I know of that is designed for your license plate is only supposed to be effective against photo-radar(Those automatic devices that take a picture of a speeding car, which allows the police to send out a ticket based on the license plate number.) The idea is that the coating somehow "blinds" the camera in regard to your license plate. Without a plate number, the police can't trace the car.
  20. Dec 26, 2004 #19


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    Lets see those pigs try and catch me in my B-2.

    Although, it might be a little difficult to drive around in downtown miami during rush hour.
  21. Dec 26, 2004 #20


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    Some types of hair spray (along with many commercially available coatings) are alleged to reduce the efficacy of a gatso/truvelo style camera being able to read your number plate, however this is nothing to do with the radar itself (which is of course merely the mechanism used to trigger the camera sequence).
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