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Which way does current flow??

Discussion in 'General Electronics Chat' started by Peter_wadley, Jul 5, 2007.

  1. Peter_wadley

    Peter_wadley New Member

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    Understanding, well for me, the way in which electronic components work is alot easier when it is presented like this:

    Capacitors

    Knowing exactly where the energy is makes it alot easier to grasp how caps work. (refer to first and second diagrams)

    Here is a question which probably doesnt deserve a thread for it self..

    In diagram 2..

    When the cap is charged and the battery is replaced with a wire.. do the electrons JUMP from one plate to the other through the dielectric?

    or

    Do the electrons go through the lamp to the other plate?

    thanks
     
  2. JimB

    JimB Super Moderator Most Helpful Member

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    Your original question:
    seems to have been answered. To summarise:

    Electrons flow from -ve to +ve.
    Conventional current flows from +ve to -ve.

    When trying to understand the operation of a particular item of electronics, just use whichever idea is easiest to understand. As long as you are consistent in the method used in each situation, it will work out correctly.

    Hero and Tomble explained it quite adequately.
    So why the temper tantrum?

    JimB
     
    Last edited: Jul 10, 2007
  3. Peter_wadley

    Peter_wadley New Member

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    Please explain how Ive managed to through a tantrum?

    What, I can't disagree with fact lacking posts like Tombles'?

    Dont get me wrong, I very much am greatful for those trying to help me understand. This topic seems to be more about personal preferences then anything also so i guess there really is no 'right' answer.

    Just trying to have a mind expanding conversation about electronics.
     
  4. dave

    Dave New Member

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  5. things

    things New Member

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    HMMMM, i didn't know that electrons flowed - to +??? stupid science books:D
     
  6. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Struck me as a tantrum!, he gave you the correct answer!.

    Current flows from +ve to -ve.

    Electrons flow from -ve to +ve.

    And it makes no difference whatsoever to designing or understanding circuits, I never even consider it either way - just that current flows from high voltage to low voltage - so from +ve supply rail to ground it's conventional current flow, and from a -ve supply rail to ground it's electron flow, it makes no difference which it is.
     
  7. Peter_wadley

    Peter_wadley New Member

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    Yes, im beginning to see that.

    I think I just associated electrons as being the only important charge.. guess not.
     
  8. Hero999

    Hero999 Banned

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    I can see your point Peter, I really can. If you're looking at how semiconductors, capacitors, batteries, i.e. how components work internally understanding that electrons flow from negitive to positive is really important.

    I just want to to see myself and Tomble's point: If all you're doing is looking at a circuit, as far as you're concerned, all the components are black boxes and it doesn't what's happening inside them. Therefore it doesn't matter which way current flows, it can flow either way, providing you keep it consistent when you are looking at the same circuit, it really doesn't matter.
     
  9. Blatman Bond

    Blatman Bond New Member

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    Its so simple, don't make it so confused. Current flow when there are different potential between conductive or resistive line. What about capacitor? Capacitor charged with current, and current always flow by different potential. I(c)=C*dv/dt.
    555 is simple too. Based on hysteretic system comparator.
    Inductor more hard to understand for beginner (charged with voltage, instant discharge when open, and its current doesn't change when shorted). V(L)=L*di/dt.
    Also Inductor and capacitor connected and transformer. But there always easy way to analyze them.

    N-type semiconductor has lower resistance than P-type. That's why N-channel mosfet most used for switching (smaller faster). Switching with mosfet is about to creating channel.
     
    Last edited: Jul 11, 2007

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