Physics

# Braking Distance and Reaction Time

Tweet
Holly Golightly's image for:
"Braking Distance and Reaction Time"
Caption:
Location:
Image by:

How often have you found yourself tailing the car in front of you? Be honest.

Braking distance and reaction time is something that we all tend to forget when driving along in our haste to get to wherever we are going.

The trouble is you should always anticipate the driver in front of you and what they might do (unexpectedly), you have to keep your wits about you when driving and again it is so easy to lose concentration when you are trying to remember shopping lists, schedules, etc.

Reaction times can also be affected if

1. You are tired (in which case you should not be driving)
2. Noisy children in the back
4. Playing loud music
5. Having an argument
6. All weather conditions
7. Day or night time driving
8. Mobile phones (are you on hands free?)and if not you should not be talking on the phone

According to the Highway Code in England and really depending on the weather conditions the braking distance is set as:

20 mph (32km/h) 6m + 6m = 12m or 3 car lengths
30 mph (48km/h) 9m + 14m = 23m or 6 car lengths
40 mph (64km/h) 12m + 24m = 36m or 9 car lengths
50 mph (80km/h) 15m + 38m = 53m or 13 car lengths
60 mph (96km/h) 18m + 55m = 75m or 18 car lengths
70 mph (112km/h) 21m + 75m = 96m or 21 car lengths

Having recently traveled on the M6 coming back from Yorkshire to Manchester, I was appalled at the number of drivers who passed us by tailing the vehicle in front of them. I was even more horrified by the fact that the weather was absolutely pelting down with rain and if there had been an accident that quite a few cars would have been involved in an accident that could have been avoided, if the drivers of each car tailing as they were pulled back a bit.

The above speeds also reflects reaction time as road surface can also alter your brake control as the safest way to brake is early and gently and brake more firmly as you begin to stop and then ease off the brake to avoid a jerky stop.

Obviously in an emergency you have to brake hard, but if you do so, try not to do so too hard as this will lock your brakes and you will lose control of the car.

Most skids are caused by the driver braking, accelerating or driving too harshly or too fast. If you go into a skid, release the brake pedal turn the steering wheel into the direction of the skid i.e. if the skid is veering to the right, turn the wheel to the right to recover.

Most people make the mistake in turning to the left and this is when the car can go into a spin.

You are never going to stop some people from driving so close that you feel they are a trailer to your car, and what makes them possess to do this I have no clue, but on the road you are driving a lethal weapon.