Facts about Speed and Time

Written by Russell Baillie

F. A. S. T.  

Facts about Speed and Time

 

No doubt we’ve all witnessed vehicles following way too close on all streets and roads and more concerning on highways and motorways. Its a real head shaker when you see vehicles near you following the car in front by around two or three metres at 110 km per hour! Call it straight out aggression mixed with a sense of entitlement, it is a disaster waiting to unfold. The most common accident in traffic is a rear end collision, or nose to tail, accounting for just under a third of all accidents in Australia.

 

Cruising down the highway with windows up, air con on and music going, most drivers underestimate how fast the vehicle is moving. Here are some simple facts as to how far a car may travel in one second –

 40kmph= 11 Metres     
50kmph= 13.9 Metres   
60kmph = 17 Metres {think 2 Council Buses}
 
80kmph =22.2 Metres [Think close to a cricket pitch} 
100kmph =27.8 Metres {think Basketball court}
110kmph =30.5 Metres {think a Netball court}
(Source: Facts and figures quoted are sourced from The Driver Trainers Manual—Allen A Brown)

 Added to the fact the vehicle is moving these distances at certain speeds, we have to take into account the reaction time as it takes around .75 of a second to take the foot off the accelerator and apply the brake. Plus the same amount of time to decide how much to apply the brake and steering decisions. So at 100kmph the vehicle would of travelled 41 metres in this 1.5 seconds of reaction time BEFORE the vehicle starts to slow.

So the Maths simply don’t add up if something suddenly happens if there is a three metre gap on the highway. At 100kmph the braking distance is 52 Metres! Double the speed equates to 4 times the braking distance and also 4 times the force of impact. At 40kmph the braking distance is 9 Metres, at 80kmph its 36 Metres.

So when Students comment how slow 40kmph is when driving thru a School Zone, its timely to point out the car is moving just about the distance of half a cricket pitch in just one second of time. 

Of course with all the wet weather we have experienced lately, the following distance should double if the roads are wet. Please Student Drivers, let’s not follow these dangerous traits and keep a larger and safer following distance. You don’t arrive at your destination that much earlier.

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