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===About Braking Distance===
'''Braking distance''' makes up one of two parts of the [[Stopping Distance|stopping distance]] of a vehicle.
'''Braking distance''' depends on:
*The [[speed]] of the vehicle - The greater the [[speed]] the larger the '''braking distance'''.
*The conditions of the road and tyres - The less [[friction]] between the road and tyres the longer the [[Braking Distance|braking distance]]. Water, oil or ice on the road all reduce the [[friction]] between the tyres and the road, causing the '''braking distance''' to be greater than for a dry road.: Different road surfaces have different amounts of [[friction]]. The painted lines on the road and the metal of a manhole cover are both low [[friction]] surfaces which are especially dangerous for motorcycles which only have two wheels (at least with 4 wheels a car will have 3 of them on the normal road with 1 on the slippery surface of a line or manhole cover).*The condition of the brakes, if they are in poor condition there will not be enough [[friction]].*The [[mass]] of the car. The more [[mass]] a car has the more [[force]] is required to slow it down so brakes providing a constant [[force]] won't be as effective. ''Higher: See [[Inertial Mass]]''.*[[Weather]] conditions - Ice reduces friction with the road making braking distance longer.
{| class="wikitable"
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Braking distance, pages 220-221, Gateway GCSE Physics, Oxford, OCR '']
:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Braking distances, page 210, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']
==Key Stage 5==
===Meaning===
[[Braking Distance|Braking distance]] is the distance traveled by a vehicle in the [[time]] taken to stop it.
===About Braking Distance===
*[[Braking Distance|Braking distance]] depends on the vehicle's speed, mass, and the condition of the brakes.
*The [[Braking Distance|braking distance]] of a vehicle on the road is affected by road conditions, tire quality and the conditions of the brakes.
*[[Braking Distance|Braking distance]] is part of the total [[Stopping Distance|stopping distance]], which also includes [[Thinking Distance|thinking distance]] with depends upon [[Reaction Time|reaction time]].
===Formula===
[[Braking Distance|Braking distance]] can be given by the formula:
<math>s=\frac{𝑣^2}{2a}</math>
Where:
s is the [[Braking Distance|braking distance]]
𝑣 is the initial [[velocity]] of the [[object]]
and
a is the [[acceleration]] of the [[object]] (in this case it is referred to as deceleration and if the velocity is chosen to be in a positive direction, the acceleration must be given a negative value).
When considering the [[friction]]al [[force]]s involved between surfaces such as the tyre and the road surface for a car then then [[Braking Distance|Braking distance]] can be given by the formula:
<math>s=\frac{𝑣^2}{2𝜇𝑔}</math>
Where:
s is the [[Braking Distance|braking distance]]
𝑣 is the initial [[velocity]] of the car
μ is the [[Coefficient of Friction|coefficient of friction]]
and
g is the [[acceleration]] due to [[gravity]] or [[Gravitational Field Strength]].
===Examples===
*At higher speeds, the [[Braking Distance|braking distance]] increases significantly.
*Wet or icy roads increase the [[Braking Distance|braking distance]] due to reduced [[friction]].