Search results
Results From The WOW.Com Content Network
Braking distance refers to the distance a vehicle will travel from the point when its brakes are fully applied to when it comes to a complete stop. It is primarily affected by the original speed of the vehicle and the coefficient of friction between the tires and the road surface, [Note 1] and negligibly by the tires' rolling resistance and vehicle's air drag.
d MT = braking distance, m (ft) V = design speed, km/h (mph) a = deceleration rate, m/s 2 (ft/s 2) Actual braking distances are affected by the vehicle type and condition, the incline of the road, the available traction, and numerous other factors. A deceleration rate of 3.4 m/s 2 (11.2 ft/s 2) is used to determine stopping sight distance. [6]
The rule is not a guide to safe stopping distance, it is more a guide to reaction times. The two-second rule tells a defensive driver the minimum distance needed to reduce the risk of collision under ideal driving conditions. The allotted two-seconds is a safety buffer, to allow the following driver time to respond.
Road slipperiness can be measured either in terms of the friction between a freely-spinning wheel and the ground, or the braking distance of a braking vehicle, and is related to the coefficient of friction between the tyre and the road surface. Public works agencies spend a sizeable portion of their budget measuring and reducing road slipperiness.
British Railway Class 90 infobox showing brake force Brake force to weight ratio of the Class 67 is higher than some other locomotives. In the case of railways, it is important that staff are aware of the brake force of a train so sufficient brake power will be available to bring the train to a halt within the required distance from a given speed.
While a corner sight distance which far exceed the braking distance at the design speed should be afforded to the driver, he or she is still generally required to maintain such control and safe speed as to be able to stop within the assured clear distance ahead (ACDA), [28] [29] [30] and the basic speed rule always applies. Jurisdictions often ...
A 1000 kg car can depress a 185/65/15 tire more than a 215/45/15 tire longitudinally thus having better linear grip and better braking distance not to mention better aquaplaning performance, while the wider tires have better (dry) cornering resistance. The contemporary chemical make-up of tires is dependent of the ambient and road temperatures.
For heavy duty commercial vehicles it is recommended 4-6 seconds following distance for speeds under 30 mi/h (48 km/h), and 6-8 seconds following distance for speeds over 30 mi/h (48 km/h). [9] Rear-end collisions are the number one type of traffic collisions .