Recent content by Nogoodnames

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    Is current harmful when it doesn't flow out of you?

    If I am not grounded (eg stand on a plastic stool) and touch a Van de Graaff generator, is it reasonable to model myself in this case as a capacitor? (using equations like I=(V/R)exp(-t/CR)) If I touch the Van de Graaf generator with a metal rod (still standing on the plastic stool), can I...
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    Is current harmful when it doesn't flow out of you?

    Yeah I don't really know how long the current flows for so I just plugged in a few small numbers. Do you know approximately how long that current flows usually? Nvm I figured out how to work out the time.
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    Is current harmful when it doesn't flow out of you?

    Sorry to keep bothering you but what equations would you use for the current induced from when the bird first comes into contact with the line until the potential between them are equalised? You seemed to imply treating the bird like a capacitor using Q=(V/R)exp(-t/CR) isn't correct?
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    Is current harmful when it doesn't flow out of you?

    If the line was 20000V but DC, would I = C dV/dt still work and would the bird still not fry? If so what would the maximal voltage gradient be? Also can you explain how you got the 10ms there.
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    Is current harmful when it doesn't flow out of you?

    You know how Q=(V/R)exp(-t/CR) so I=-(V/R)(1/CR)exp(-t/CR), so the integrand of RI2=0.5*V2(1/CR)exp(-2t/CR) How do these numbers work out to show the energy dissipated is small?. In particular, if the capacitance is small (ie not so different from radius of bird*4*pi*8.85x10^-12, permitivity of...
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    Is current harmful when it doesn't flow out of you?

    So it's the energy loss of current that potentially does the damage to the bird? In calculus terms, Q is proportional to exp(-t/CR), you differentiate this with respect to time to work out the current I. Is the total energy dissipated from t=0 to t=T the integral with respect to time of (R*I^2)...
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    Is current harmful when it doesn't flow out of you?

    I think I get it now, the bird feels an energy of E=QV=CV^2 and because capacitance is small, the energy is small?
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    Is current harmful when it doesn't flow out of you?

    Yes but doesn't voltage or potential difference depend on the amount of charge? Potential difference is the line integral of electric field and electric field depends on the charge density by Coulomb's law or superposition principle?
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    Is current harmful when it doesn't flow out of you?

    I don't know much about capacitance but if the birds cannot store much charge, how does it achieve the same high voltage as the power line? From what I understand voltage=potential difference is the amount of energy needed to bring a unit positive charge from one point to another (in this case...
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    Is current harmful when it doesn't flow out of you?

    I assume it's because the bird has the same voltage as the power line which is why it lives. Do you know how the bird reaches the same voltage as the 20,000 V power line though? I am guessing there must be a brief exchange of charges between the power line and the bird to achieve this? If so...
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    Is current harmful when it doesn't flow out of you?

    An unsteady current (or electrostatic shock if you prefer) induced by touching a conductor of higher potential, that quickly dissipates inside you as the charges move to reach equilibrium.
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    Is current harmful when it doesn't flow out of you?

    Interesting video, although I was asking whether or not a current that doesn't flow out of you would harm you, without any protection like a Faraday cage.
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    Is current harmful when it doesn't flow out of you?

    Sorry by 'discharge' do you mean charge going from a source to the electric component or from the electric component to some lower potential? In other words do electrical components get damaged if they get charged up to quickly?
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    Is current harmful when it doesn't flow out of you?

    Thank you for the reply. So in general, electrical components (even 'delicate' ones eg RAM inside the computer) can happily build up charge?
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