234 km/h

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Mefiante (December 06, 2010, 15:50:33 PM):
If you include "reaction time/distance" in the formula, then yes.
You can derive the formula from first principles with a basic knowledge of high school kinematics. The formula is (and you can check its validity for yourself by dimensional analysis):

sS = v0∙tR + ½∙m∙v02/FB

where

sS ― total stopping distance (metres);
v0 ― velocity of the vehicle before braking commences (metres per second);
tR ― driver’s reaction time (seconds);
m ― vehicle’s mass (kg); and
FB ― constant braking force (Newtons).

For example, a 1,500 kg vehicle travelling at 34 m/s (= 122 km/h) whose brakes and tyres are capable of exerting 10 kN (= 10,000 N) of braking force will have a total stopping distance of about 104 metres if the driver’s reaction time is half a second. At half that speed with everything else being equal, the stopping distance is a little over 30 metres. At twice the speed, the stopping distance is 381 metres.

Clearly, the dominant term on the right-hand side is the second one, which is quadratic in v0, and if you neglect the reaction time, the first term on the right-hand side falls away completely, making the formula a pure quadratic in v0.

'Luthon64
Lilli (December 07, 2010, 08:26:54 AM):
Regardless of the fancy mathematics - fact remains: it is not speed that kills. It's stopping very suddenly that's the bitch... ;D
StevoMuso (December 08, 2010, 10:17:19 AM):
Regardless of the fancy mathematics - fact remains: it is not speed that kills. It's stopping very suddenly that's the bitch... ;D
LOL. Good one Lilli. Maybe it's how fast you stop that kills, heheh.
Tweefo (December 08, 2010, 17:50:18 PM):
In my skydiving days I've seen (twice) what the last cm can do. Not a pretty sight. :(
Watookal (December 08, 2010, 21:05:30 PM):
I bet that leaves quite an impression.

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