Electrical Safety

Voltage without current, otherwise known as static electricity....

Voltage requires charge displacement.

Why do you think you go "ouch!"

So-called "Static" electricity is just a build-up of voltage through charge separation. Lightning is "static" electricity. Within the realm of everyday life, I had a car that would just about knock me on my behind on dry days as I was getting out.

polymorph:
Within the realm of everyday life, I had a car that would just about knock me on my behind on dry days as I was getting out.

I learned to keep my hand on some part of the metal as I slide out. This allows a small current to flow over the time it takes to get out of the car instead of one enormous current when you shut the door. Insulation-blowing machines can also create giant 6" sparks from their hoses on dry days. It is quite surprising when you walk too close to one to say the least.

I got into static back in school over 40 years ago though I never built a generator.
Voltage is electrical potential.

If you work in a place with compressed air to run machines with, it's got a little oil in it, then take a plastic bowl and give it a good spraying. Then find a victim, smile, point into the bowl and say "juice" but don't say touch or not, let them stick a finger in to show you there's no juice in that bowl. ]:smiley:

InPhase277:
I learned to keep my hand on some part of the metal as I slide out. This allows a small current to flow over the time it takes to get out of the car instead of one enormous current when you shut the door. Insulation-blowing machines can also create giant 6" sparks from their hoses on dry days. It is quite surprising when you walk too close to one to say the least.

I do exactly the same when the weather is dry, otherwise I can draw a spark that makes my arm buzz to the elbow!
:astonished:

I actually think, that I and the car work as an electrophorus, unless the electrons are allowed to flow back slowly.

And in dry weather, I touch the door handles at work with my keys or a penknife before opening the doors at work. I can draw a couple of cm long sparks on a "good" day.

how about attaching a small neon bulb to the car, to absorb any static build up?

How would you attach the bulb?

cjdelphi:
how about attaching a small neon bulb to the car, to absorb any static build up?

I think the problem is, that the charge build up is between the driver and the seat.

My hineys are busy rubbing electrons off the seat while driving, and when I get out, the charges are separated.
That also explains, why the effect of the "lightning rod" some people attach to their cars, is quite limited.

Wearing plastic fiber clothes don't help.
I spent time at the local VA where the carpets were like some kind of Van Der Graff belt. Get up to a door and the habit is to grab the handle and get zapped. I took to touching the painted part of the metal door and while no zap, I could feel the effect of the charge bleed (human, I feel it after it's happened as if it still is). Some time in the past the DoD bought a bazillion gallons of oil based paint and it makes a good resistor.

I have a scare when there's casual static because I am a computer user.

But there is some fun to it!
Sneak up to a friend, and touch a finger to his ear.
]:smiley:

When my kids were small, they had a plastic chute for playing. Sometimes they played "Pikachu", meaning that one of them would slide halfway down and stop, then touch a finger to the nose of the other, standing next to the slide, and draw an audible spark.
They considered it great fun.

fungus:
- YouTube

My goodness!
:astonished:

what was that?
Had he thrown some kind of conductive string over the wires?

fungus:
- YouTube

Then later to complain about poor electrical service. It is way.

After thinking about it, the neon bulbs would have to be connected inside door frames so it sits between you and the car ... not as straightforward as I thought at 3am

Actually, while you are in the car, you have no charge (assuming you are touching the key in the ignition or some other metal part.

The car picks up charge as it moves through the air, and probably some interaction with the tires.

When you step out, you discharge the car. It isn't actually you that has the charge built-up. So what you need to help keep the car discharged is a light wire or chain hanging down.

They used to be called ground straps.

polymorph:
Actually, while you are in the car, you have no charge (assuming you are touching the key in the ignition or some other metal part.

The car picks up charge as it moves through the air, and probably some interaction with the tires.

When you step out, you discharge the car. It isn't actually you that has the charge built-up. So what you need to help keep the car discharged is a light wire or chain hanging down.

There are two theories, and you represent one of them here:
"The charge buildup is between the car, and the rest of the world. You get zapped, because you form the path to discharge the car"

The other one is:"The charge build up is between you and the car. When you get out, you separate the charges, increasing the voltage. The discharge is between you and the car"

I believe in the second explanation.
(And I have had ground straps on cars. In my case, they didn't work at all)

Peter_I, I think both are correct. It just depends on the vehicle and the conditions.

I've had cars where I'm sure it is the vehicle building the charge. I can touch metal inside, nothing happens. I slide around without getting out, I can touch metal and nothing happens. But if I get out with a hand on metal I can feel a big Snap through my shoe to the ground. And if I get out without touching metal, I don't get zapped until I touch the car.

Other vehicles, I think it is me sliding across the seat, because I won't get shocked if I touch the keys while still inside, but if I start sliding around and -then- touch metal, I get a spark while still inside. If I get out without touching metal, sometimes I can detect a spark through my foot to the ground, and another spark when I touch the car. That would seem to indicate I have the charge.

Between they key/ignition a neon bulb should sit the last thing to do after stepping out is get the key which discharges static build up then?

I don't think the neon bulb is necessary, except as an indicator that there was a discharge. The current is low enough that you only feel the spark because it is very concentrated where it hits you. So in that sense, holding the neon bulb is as good as holding a key, coin, or other metal object.

There is always that "wireless" antistatic wrist strap... smirk.