R

#### [email protected]

- Jan 1, 1970

- 0

icumen in, but do you youngsters *know* about it?

E.g. you know that its a lot more fun discharging a small 370V

capacitor than a *huge* 5V one because energy is proportional to the

voltage *squared* (because if you double voltage then the current

doubles too and energy is their product)because

Energy = CV^2

I

-------------

| |

| |

V | Energy |

| |

| |

| |

-------------

The same thing applied to speed. If you double the speed you quaduple

the energy because Energy = MV^2

So if you hit a massive artic' while doing 1 mph (the lorry is

stationary) on yer bike then (assuming you weight "one" unit) you will

dissipate one unit of energy.

If you hit the same vehicle at 101 mph when it is doing 100 mph then,

ignoring the lorry's slight speed increase, you will dissipate the

difference between you doing 101 and 100 i.e.

101*101 - 100*100 == ~200

That's nearly 200 hundred times more dangerous.

Wazzat? ya don't believe it? (The local boy racer is reading this over

my shoulder, he is snorting disbelief). Well if you prefer a belief

system to a mathematical system then look at it this way: How much

energy do you have to put it to get ya bike up to 1 mph? Not much, you

just start pushing it and after a couple of strides both of you are up

to 1 mph but what about 100 to 101? First of all you have to *be*

running at 100 *before* you start pushing and *then* you must push and

get it to 101. The ground you have to cover *while* pushing is

evidently a hellofalot more. Does that not seem like a *lot* more

stored energy to you?

Cheers

Robin Pain (ouch)