Speed ​​imposes a handling problem on us: The faster we are on the move, the stronger the increasing energy we have to be careful with. Because it is energy that can be dangerous to us if handled improperly.

The former TopGear icon Jeremy Clarkson makes his very own contribution to the discussion: “Speed ​​has never killed anybody. Suddenly becoming stationary, that’s what gets you.” In German roughly: speed has never killed anyone. It’s the sudden standstill that gets you. He’s right, because how should you fly with 900 Survive km / h when speed kills per se? However, Jeremy meant something else in this context: He was annoyed about some speed limits in the UK, which he thought were completely excessive.

Sudden standstill I find the point with the sudden standstill very worth explaining. It provides findings that are almost more important for the booming field of bicycles and e-bikes than for cars. Hence, according to Jeremy, kinetic energy is best thought of as impact energy. In other words, as the energy that has to be used up again when I hit something head-on. Which I or my counterpart get to feel when it really cracks.

But even that remains very diffuse. A table, however, which lists the impact force corresponding to the speed, makes it clearer in my opinion. Its content is calculated very simply using the formula

E = 1/2 mv 2

E stands for energy, m for the moved mass and v for the speed. Neither the constant 1/2 nor the mass is relevant if you just tabulate the energy differences at different speeds , because the constants 1/2 and m are shortened away. What remains are very simple numerical relationships. The table shows the speed in km / h and on the right the increase in energy in the square; For the sake of simplicity, I have introduced the dimensionless energy factor EF .

v EF 10 15 20 25 30 100 225 400 625 900 40 45 50 60 70 1600 2025 2500 3600 4900 80 90 100 110 120 6400 6400 10 000 12 100 14 400 130 140 150 200 250 16. 9 19 600 22 500 40 000 62 500 According to my observations ungen is today however 15 km / h is more like the average speed, thanks to smooth running bikes with many gears. An increase to 20 km / h also doubles the energy here, at 25 km / h she is already opposite 15 km / h tripled. (225 x 2 = 450, 225 x 3 = 625, whereby – as a reminder – 225 the energy factor EF at 15 km / h is).

Anyone who treats themselves as an e-bike to a speed pedelec that will take the driver to 45 km / h, which is nine times the impact force towards the leisurely cyclist with 15 km / h on the way. This of course also applies to amateur cyclists who juggle at such a pace on extremely delicate equipment under their very best.

Accelerated seniors How many bicycle sellers support seniors who live with a pedelec (up to 25 km / h) or even want to facilitate e-bikes, give an adequate assessment of the risk potential? After all, a number of municipalities have recognized the problem insofar as they offer suitable training courses for cyclists.

In the meantime, falls and collisions with fast bicycles can have fatal consequences – and that without any help of motorists. The accident statistics 2018 for Lower Saxony already names noticeable increases in fatal accidents for Seniors with e-bikes, however, does not break down the parties involved in the accident separately.

Well, and whoever is allowed to share the paths with cyclists while walking in the woods (e.g. in Hanover’s beautiful city forest, der Eilenriede), feels more and more threatened by bicycle racers: They really rush past you faster and faster and you definitely don’t want to rattle together as a pedestrian.

Germany unites Raserland Then there are still these are so annoying for drivers 30 er zones, the traffic signs of which are shooting up like mushrooms in the cities. You now have a state-of-the-art car, really good brakes and a lot of assistance … still, physics tells us unpleasant things if we listen to it.