prelim physics (1 Viewer)

(^o^)

you stupid crap! *slaps*
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I doubt most of the prelim people are up to where our school is so i decided to ask here instead of gonig to the prelim forum. Hope you don't mind.
We are doing electricity and i don't get one of the dot points:

Discuss the danger of an electric shock from a 240AC mains supply and various DC voltages from various appliances on the body.

I just wrote:
It's not the voltage but the current that kills. Any electrical device used on a house wiring circuit can, under certain conditions, transmit a fatal amount of current. People have been killed by 100 volts AC in the home and with as little as 42 volts DC. The longer the exposure to the current, the more likely that death will occur. The lethal limits can falls to as low as the 50-100 mA range. (shock can cause the heart and lungs to stop functioning).

Do you think I have answered the "dot point"?
If not, what should I write?

Thanks guys :)
 
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The key idea to get across here is that only AC current can cause fibrillation, whereas DC current just burns you..


If I were you, I'd phrase it a lot differently as well.

For example, rewording your answer:

In an electric shock, whether or not death will occur depends soley on the electric current. In the right circumstances, any electrical device on a home power supply can transmit a fatal amount of current. The likelihood of death depends on two main factors, the size of the current supplied, and the length of exposure to current. As the length of exposure increases, the likelihood of death increases. Lethal amounts of current can be as low as 50-100mA, where the current is sufficient to cause fibrilliation.

Something like that.
 

(^o^)

you stupid crap! *slaps*
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Oh thanks "George W. Bush"
I know the wording is a bit informal as I was just doing the dot points for my own study notes. But hey your reworded paragraph is better so thanks a lot.
:)
 

xiao1985

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also, the frequency of the AC supplie used world wide ( i believe) is one that is syncrhonised with the electric impulse of human brain... incidentally... so when ever an electrocution occurs, the ac messes with the electrical signal sent by the brain... normally, since the muscle at the back of the hand is stronger, so u tend to hold into ur fist ... if u were holding the power supplie it is less likely for you to put it down...

also, it depends the V in the pwoer source and resistance (ie, condition of ur body, sweatness, wetness, skin pH etc etc) high resistance = higher chance of survival...

also the path which current goes thru... if it doesn't pass ur heart, you are less likely to die...

btw smilie face, cum bak to chinese forum... and let us 03'er continue to corrupt you >=p
 

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