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Author Topic: Uncertainty about speed cameras  (Read 6763 times)

Offline DoctorBeaver

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Uncertainty about speed cameras
« on: 18/11/2005 16:41:22 »
Doesn't Heisenberg's uncertainty principle mean that speed cameras can't work? If they measure your speed, they don't know where you are & vice versa?

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Offline Solvay_1927

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Re: Uncertainty about speed cameras
« Reply #1 on: 18/11/2005 17:13:25 »
Er, yes, but I wouldn't rely on that excuse in court, Eth - if they measure your speed accurately, they'd only know your position to within about a million-million-million-million-million-millionth of a millimetre.


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« Last Edit: 18/11/2005 17:14:04 by Solvay_1927 »
 

Offline DoctorBeaver

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Re: Uncertainty about speed cameras
« Reply #2 on: 18/11/2005 20:46:42 »
grrrrrrrrr. I must be as thick as 2 short Plancks
« Last Edit: 18/11/2005 20:47:34 by DoctorBeaver »
 

Offline Solvay_1927

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Re: Uncertainty about speed cameras
« Reply #3 on: 18/11/2005 21:51:00 »
Oh very good - "2 short Plancks" :D

I may have answered too hastily before.  The calculation above is based on a margin of error of about +/- 1 kph in the measurement of the car's speed.

If the police say that their measurement is only accurate to within a certain margin, then you're done for.  But if you can trick them into saying that they're "absolutely 100% certain" what your speed was, then you can invoke the Uncertainty Principle to argue that they couldn't possibly know what your position was (i.e. that they have no way of knowing if that was your car in the picture).

I suggest you try this defence next time you're up in court for speeding. You never know, you might get a magistrate who's also a naked scientist or something!

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Offline Solvay_1927

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Re: Uncertainty about speed cameras
« Reply #4 on: 18/11/2005 21:55:38 »
Come to think of it, there's another thing you can try - just claim that your car only weighs, say, 10^-40 kg - which would also give you a large uncertainty in position.

(And if they don't believe you and want to weigh the car for themselves, you could just say you've since lost the car. Maybe it blew away in the wind or something.)
 

Offline neilep

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Re: Uncertainty about speed cameras
« Reply #5 on: 18/11/2005 22:56:57 »
Can't you just say it was the Speed Camera that was speeding !!!

I've got two lots of three points on my license because of those friggin things.....both sets obtained on the M25 at 2 and 3am in the morning ,one year apart,as a controlled speeding zone was opening back up to three lanes ! with a clear road infron of me, and no one behind I was doing 55 instead of 50 and 44 instead of 40 !!...and that's the truth !!...

.....Only yesterday I heard on the news that the latest stats are that there has been a massive increase in the number of people getting points on their license due to speed cameras !!....

(Dear lovely Americans...the M25 is a motorway ...sorry..Freeway !)

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Offline DoctorBeaver

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Re: Uncertainty about speed cameras
« Reply #6 on: 18/11/2005 23:10:05 »
In a test on TV the other day a hand-held speed camera of the type the police use showed a stationary car to be moving at 6mph. If the camera isn't held completely still (not easy with a hand-held) and the operator moves the camera down even fractionally, the Doppler effect shows the car moving faster than it actually is.
Add that 6mph error to a car doing 28mph in a 30 limit & you've got a fine for speeding. Not good.
Could I claim that there was uncertainty about the position of the camera?
 

Offline DoctorBeaver

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Re: Uncertainty about speed cameras
« Reply #7 on: 18/11/2005 23:12:28 »
Neil - I got nicked for speeding in Mablethorpe, Lincs, in a 30mph zone when I was actually travelling at about 15mph. A car overtook me & then immediately turned left. I was the next car past the end of the speed trap so I got done for it. grrrrrrrrr
(I was travelling so slow because I was looking for a small sign pointing to the dune buggy racing)
 

Offline neilep

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Re: Uncertainty about speed cameras
« Reply #8 on: 19/11/2005 00:06:34 »
Eth...that is so not fair...in reality there's sod all you can really do about it eh ?..because they have the ' photographic ' evidence to back them up......did you think about contesting it ?

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Offline DoctorBeaver

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Re: Uncertainty about speed cameras
« Reply #9 on: 19/11/2005 01:10:56 »
Neil - I DID contest it. I drove from London to Mablethorpe to contest it!
I was working for Lucas Defence Systems at the time & 1 of our microwave engineers had worked on the design of speed cameras. He gave me all the technical data on them - how & where they should, or should not, be used; how they could give false readings etc - but the magistrate wasn't interested. I got fined & points.
 

Offline neilep

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Re: Uncertainty about speed cameras
« Reply #10 on: 19/11/2005 03:40:14 »
Eth...That's a right pain the arse !...I'm afraid to say I'm not surprised.....and you pay for it twice as it puts your insurance premium up too !....

...Was that at Lucas Defence in Hemel Hempstead ?

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Offline doughnut

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Re: Uncertainty about speed cameras
« Reply #11 on: 19/11/2005 11:48:05 »
I've got two lots of three points on my license because of those friggin things.....both sets obtained on the M25 at 2 and 3am in the morning ,one year apart

Each set obtained at 2 AND 3 am.  Therefore 6 points in each set.
Two sets, giving 12 points and... You aren't driving on a ban are you?
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Offline DoctorBeaver

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Re: Uncertainty about speed cameras
« Reply #12 on: 19/11/2005 12:35:51 »
Neil - Neasden. We were a seperate dept in a company called G & E Bradley. We did a lot of work for Marcel D'assault.
 

Offline neilep

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Re: Uncertainty about speed cameras
« Reply #13 on: 19/11/2005 14:42:36 »
Doughnut...one set at 2am one year, the next set at 3am the following year...6 points !...my fault for not explaining it correctly.......from now on I am a model driver , even when I have the whole damned motorway to myself, which means I'll be on the road longer and will have more chance of having an accident !

Eth, thanks for the clarity, in a past life I had a lot of dealings with defence orientated companies.....which is nice !

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Offline DoctorBeaver

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Re: Uncertainty about speed cameras
« Reply #14 on: 19/11/2005 17:05:53 »
I susequently worked for MSDS on Stingray torpedoes
 

Offline neilep

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Re: Uncertainty about speed cameras
« Reply #15 on: 19/11/2005 17:47:40 »
quote:
Originally posted by DoctorBeaver

I susequently worked for MSDS on Stingray torpedoes



I dealt with them in Stanmore and Waterlooville.

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Re: Uncertainty about speed cameras
« Reply #16 on: 19/11/2005 19:26:28 »
I was based at North Wembley but had to go to Stanmore quite a lot
 

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Re: Uncertainty about speed cameras
« Reply #16 on: 19/11/2005 19:26:28 »

 

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