QUOTE (NJL @ Jul 14 2009, 01:44 PM)

Just drive it onto a piece of corrogated iron and ground a car battery onto that same sheet. If someone steps on it without proper shoes, zappimus maximus.
On second thoughts, do not do that, that is illegal and someone will probably die.
um no.....
it won't zapp anyone,
you can not get a shock out of a 12 Car volt battery, you do realise you can hold the terminals on a car battery????
a bit of cut and paste reading for you
If 240 amps passes through any significant amount of a human body for any significant period of time, investigators may have to employ DNA analysis to determine who that stuff they found all over the place used to be. You really don't want to make yourself part of a 240 amp circuit. Actually, only about 30 milliamps (0.03 amps) across the human heart has a good chance of stopping it.
Where people go wrong, here, is by thinking that if you disconnect one battery lead in your car, hold the end of that lead in one hand, touch the battery terminal with the other hand, shout "Je ne regrette rien!", and then get a partner in scientific exploration to turn the ignition key, you'll be deader, faster, than someone who's already started his skydive when he discovers that the thing on his back actually contains some chocolate and a sleeping bag.
What will actually happen in the above situation - the car situation, not the skydiving one - is nothing.
The reason for this is that the human body has quite a lot of resistance of its own. If you've got a good contact - the terminals are big enough that the whole palm of each hand can touch them - then the resistance across your body is likely to be between about 2,000 and 50,000 ohms. The thinner and wetter your skin, the lower the resistance will be.
Even if your resistance is only 2000 ohms - which it probably won't be - that's enough to drop the circuit current to about 6mA. You may be able to feel that. You probably won't.
Since your resistance is actually likely to be much higher, the current through your body is likely to be trivially low. And since your body is part of the circuit, the current through the whole circuit will also be trivially low. Hence, the car will not start, and you will not die.