Bicycle Safety - The Math of Speed

[The fingers]

I went to Tucson the speed limit is 15mph at the school zone with 2- 4way stop signs took 20min's because there was no GO sign.

GO signs seem to be needed in many places, especially where the road comes to a T and the right and left sides have stop signs. :wink:
At least some freeway onramps have green lights at certain times. Unfortunately, people randomly stop at green lights and run red ones. :x

 

[DrkAngel]

Fall = Impact speed - analogy

"A fall off a 3.3 feet desk results in a speed at impact of 10 m.p.h.
A 10 m.p.h. change in speed (Delta-V) in a motor vehicle collision is equivalent to falling off a desk.
Similarly,
a 15 m.p.h. change in speed is equivalent to falling 7.5 feet - off a step ladder.
A 20 m.p.h. change in speed is equivalent to falling 13.4 feet - off the roof of a one story building.
A 25 m.p.h. change in speed is equivalent to falling 20.5 feet - off a two-story building.
A 30 m.p.h. change in speed is equivalent to falling 30 feet - off a three-story building."

A very relateable impact speed analogy - scientific numbers.

Wow! - Vehicular impact (from behind)
A 30mph car hitting a 20mph cyclist, from behind, is equivalent to rolling off a desk! ... ?
Compared to ...
A 30mph car hitting a 10mph cyclist, from behind, is equivalent to rolling off the roof of a house with a half basement.! ... ?

Bumps and bruises vs breaks, internal injuries and concussions ... or worse.

 

[alsmith]

The octopi-