Speed and stopping

[flint]

Interesting (well I thought so) chart on stopping distances. Overcoming kinetic energy and thinking distance means that the speed of impact does not directly correspond to road speed before braking.

 

[Chas]

Interesting (well I thought so) chart on stopping distances. Overcoming kinetic energy and thinking distance means that the speed of impact does not directly correspond to road speed before braking.
View attachment 164222

That's very interesting, so from 38mph you only lose 1mph in three car lengths? but that chart gives no indication of variables like brake efficiency, condition of tyres, condition of road surface all these things would effect the impact speed

 

[flint]

Yes, quite right, I presume that it refers to an average car in dry conditions with all components in good working order. Thinking (reaction) distance is going to be greater, but also the way that friction brakes work, i.e. if seen on a graph, it's not a straight line from when they start to bite to stopping, but more of a curve with the last part of the curve (just before stopping) being the most effective.

 

[Paddler Ed]

Don't forget that at 38mph you will cover 16m in one second: (After I had it set up in Excel, I just ran it over everything....)

38 MPH
KMH: 61.15507
Distance in one minute (KM): 1.0192512
Distance in one second (KM): 0.01698752
Distance in one second (M): 16.98752

35 MPH
KMH 56.32704
Distance in one minute (KM): 0.938784
Distance in one second (KM): 0.0156464
Distance in one second (M): 15.6464

30 MPH
KMH: 48.28032
Distance in one minute (KM): 0.804672
Distance in one second (KM): 0.0134112
Distance in one second (M): 13.4112

25 MPH
KMH: 40.2336
Distance in one minute (KM): 0.67056
Distance in one second (KM): 0.011176
Distance in one second (M): 11.176

20 MPH
KMH: 32.18688
Distance in one minute (KM): 0.536448
Distance in one second (KM): 0.0089408
Distance in one second (M): 8.9408