Why not have standard 12V DC outlets in homes instead of individual transformers

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That is an interesting anecdote, but I'm confused about how the car started with only the + terminals connected.
 
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zoobyshoe said:
That is an interesting anecdote, but I'm confused about how the car started with only the + terminals connected.

The touching bumpers provide the ground path. Must have been older type cars that had metal bumpers. Drag might have been embarresed if the bumpers had welded together! :smile:
 
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GENIERE said:
The touching bumpers provide the ground path. Must have been older type cars that had metal bumpers.
I didn't take the "touch bumpers" literally, but of course, that makes perfect sence.
 
It takes about 6 milliamps to cause serious harm. Doesn't matter if it's AC/DC, the CURRENT not the voltage, that will make you rock.
 
integral ,
i had the same doubt zooby had about the frequency being generally high and therefore not giving u enough time to remove ur hand . isn't it more realistic to consider the average over half a cycle (.707 times the maximum) for each direction?
also i didnt quite understand what u meant by muscles alternatively flexing and distending?
 
I remember when I wired my house for ethernet, a friend of mine dared me to lick my fingers and touch the bare phone wires. I was terrified of the 46V, but when I finally did it it was merely a tickle.
 
GENIERE said:
Must have been older type cars that had metal bumpers.
Yeah. I'm dating myself here. This was 26 years ago, when practically all cars had these heavy chrome-plated steel bumpers.
 
govinda said:
also i didnt quite understand what u meant by muscles alternatively flexing and distending?
If there were any truth to this it would only result in vibration of the muscles at 60hz with very low amplitude.
 
zooby ,
im sorry still don't understand what's going on with the muscle care 2 elucidate?
 
govinda said:
zooby ,
im sorry still don't understand what's going on with the muscle care 2 elucidate?
I think what Integral is saying is that once you become part of a direct current circuit, at sufficient voltage, it is the current itself that won't let you go.

From that, he argues that AC is safer because it changes direction 120 times a second and there is a point 120 times a second when the current going through you is 0 amps at 0 volts, which, he contends, gives you the chance to pull yourself out of the circuit.

My contention is that the current causes a person to clench their muscles, and it is this clenching that prevents people from getting themselves out of electric circuits, rather than being held prisoner by the current.

Dave is the one who brought up the part about flexing and extending. I think it was just speculation on his part. It takes a small amount of time for a muscle to relax once it has been clenched, and I know a human muscle can't fully relax from being clenched in 1/120th of a second. The most you might get is a vibration.