csweatherston
Member
Registered: 16th Jan 06
Location: Devon
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my girlfriend had to attend an advanced driving course today (after her accident)...instead of getting points/ going to court etc.
they presented her with this question:
look at the pic:
*the left 2 blocks are identical cars (with their speeds shown)
*the red blocks are a road accident
*the remaining blocks are stopped cars.
the question is;
when the vehicle travelling 70mph has stopped, what speed will the vehicle travelling 90mph still be doing.
(if they spot the accident and start braking at the same time)
??????
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Timbaland
Banned
Registered: 20th Jan 07
Location: Glasgow
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20mph?
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ed
Member
Registered: 10th Sep 03
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Questions like this are flawed by the fact that there are so many different factors involved with stopping a vehicle.
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S@M
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Registered: 3rd Oct 07
Location: East Yorkshire
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first thoughts would be 20 but theoretically it will be more...
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16V_1600
Member
Registered: 7th Oct 07
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Be part of the road accident.
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Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
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My guess is that they amaze everyone in attendance by telling them how much higher than 20 mph it is.
So - in a theoretical situation in which you're required to stop, you're betting going slower.
I'm shocked, honest.
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TomSBD
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Registered: 22nd Jun 06
Location: Spalding, Lincs
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0mph it hit the cars in front
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Simon
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Registered: 24th Apr 03
Location: Oxfordshire
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0 - car doing 90 will have be banjaxed and crash
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csweatherston
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Registered: 16th Jan 06
Location: Devon
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answers around 20 though yes???..
this is what i said, (and she answered in her test)..
but according to the instructors, and police the 90mph vehicle would be doing 70 when the other has stopped.
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Timbaland
Banned
Registered: 20th Jan 07
Location: Glasgow
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Is this a trick question?
Is the car travelling at 90mph a 106 GTi, Cos that could make a difference.
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Timbaland
Banned
Registered: 20th Jan 07
Location: Glasgow
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quote:
Originally posted by csweatherston
answers around 20 though yes???..
this is what i said, (and she answered in her test)..
but according to the instructors, and police the 90mph vehicle would be doing 70 when the other has stopped.
The instructors and police are wrong.
Im right.
So is your girlfriend and you.
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S@M
Member
Registered: 3rd Oct 07
Location: East Yorkshire
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na wont be that much but her 30-50 maybe
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TomSBD
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Registered: 22nd Jun 06
Location: Spalding, Lincs
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so there saying the 70 car can stop dead in the time the 90 can can brake from 90 to 70 yeh right??
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ed
Member
Registered: 10th Sep 03
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Although apparently your stopping distance is v²÷20+v.
If only it was that simple.
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csweatherston
Member
Registered: 16th Jan 06
Location: Devon
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The accident is a GTI and a VTS, the one doing 90 is a CTR @ 120000rpm and the 70 is an xe corsa with a power boost valve
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csweatherston
Member
Registered: 16th Jan 06
Location: Devon
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im tempted to write a letter actually, as she's convinced the police are correct now!
it denys the laws of physics.
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Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
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ps. the answer is that the guy paying attention in an appropriate vehicle will have stopped well in advance, regardless of their speed at any time during the journey.
The guy doing 70mph with solid discs adjusting his radio will crash massively because he is neither prepared for what is ahead or able to rely on modern technology such as huge brakes and 225 section rubber.
Same reason as the guy doing 30mph past a school at 3.30 will usually kill children.
Its complete BS. There's no science available in that question in order to answer it, same as there's no logic in relating road safety to speed limits. Complete poppycock.
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johnhara1
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Registered: 19th Oct 06
Location: Newcastle upon Tyne
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I got just under 40mph
Worked it out by using stopping distances at 70 and at 90.
Completely agree with Ian tho, too many factors to consider making that question completely pointless.
[Edited on 15-02-2008 by johnhara1]
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Ben G
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Registered: 12th Jan 07
Location: Essex
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what if the car doing 70 was a shed 1.2 corsa with shite brakes and drums and the car doing 90 was a bmw m5 with hi-spec disc's all round?
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Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
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quote:
Originally posted by csweatherston
answers around 20 though yes???..
this is what i said, (and she answered in her test)..
but according to the instructors, and police the 90mph vehicle would be doing 70 when the other has stopped.
That is theoretically correct as the thinking distance plus the distance to stop at 70 is only slightly less than the distance you will travel doing 90 whilst thinking.
I can't believe they're using some flawed crap about all things being equal. They're not. If you pay attention you generally don't crash. If you watch your speed more than oncoming hazards then you are a worse driver.
[Edited on 15-02-2008 by Ian]
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csweatherston
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Registered: 16th Jan 06
Location: Devon
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uh oh..i may be wrong 
http://www.volvoclub.org.uk/pdf/SpeedStoppingDistances.pdf
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Timbaland
Banned
Registered: 20th Jan 07
Location: Glasgow
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quote:
Originally posted by csweatherston
uh oh..i may be wrong
http://www.volvoclub.org.uk/pdf/SpeedStoppingDistances.pdf
Thats for Volvo's though. They weight the same as my house.
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S@M
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Registered: 3rd Oct 07
Location: East Yorkshire
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quote:
Originally posted by Ben G
what if the car doing 70 was a shed 1.2 corsa with shite brakes and drums and the car doing 90 was a bmw m5 with hi-spec disc's all round?
[/quote
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Jakey
Premium Member
Registered: 4th Jun 07
Location: Sandbach
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quote:
Originally posted by Ben G
what if the car doing 70 was a shed 1.2 corsa with shite brakes and drums and the car doing 90 was a bmw m5 with hi-spec disc's all round?
I'd hope i was driving the Beemer
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Ben G
Member
Registered: 12th Jan 07
Location: Essex
User status: Offline
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question is: why are are the two car's level? surely if one's doing 90mph it'd be in front of the one doing 70mph
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