National Grid

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  1. ilovemath's Avatar
    • Benevolent Member
    • Posts: 730
    National Grid
    the current we recieve from the national grid is A.C
    why then don't objects turn on and off again as the current passes through the zero point?
    (current follows a sinosidual curve)
  2. marsman13's Avatar
    • Respected Member
    • Location: London
    Re: National Grid
    Its magic.
  3. ilovemath's Avatar
    • Benevolent Member
    • Posts: 730
    Re: National Grid
    (Original post by marsman13)
    Its magic.
    ???
  4. Stonebridge's Avatar
    • Community Assistant
    • TSR Demigod
    Re: National Grid
    (Original post by ilovemath)
    the current we recieve from the national grid is A.C
    why then don't objects turn on and off again as the current passes through the zero point?
    (current follows a sinosidual curve)
    Because they operate on DC and have built in transformers (to step down the voltage) and a rectifier and smoothing circuit (capacitor) to change it to DC.

    You asked a question related to this recently.
  5. ilovemath's Avatar
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    • Posts: 730
    Re: National Grid
    (Original post by Stonebridge)
    Because they operate on DC and have built in transformers (to step down the voltage) and a rectifier and smoothing circuit (capacitor) to change it to DC.

    You asked a question related to this recently.
    I was not aware of the connection
    thanks for this
  6. Stonebridge's Avatar
    • Community Assistant
    • TSR Demigod
    Re: National Grid
    (Original post by ilovemath)
    I was not aware of the connection
    thanks for this
    By the way, the stuff that does work on AC, an electric fire for example, doesn't notice the change in the current because it gets hot whichever way the current goes. The change is so rapid, at 50Hz, that the fire doesn't have time to cool down between cycles.
  7. ilovemath's Avatar
    • Benevolent Member
    • Posts: 730
    Re: National Grid
    (Original post by Stonebridge)
    By the way, the stuff that does work on AC, an electric fire for example, doesn't notice the change in the current because it gets hot whichever way the current goes. The change is so rapid, at 50Hz, that the fire doesn't have time to cool down between cycles.
    thanks for this
    I guess with a Frq this fast it would be impossible for the circuit to change or for us to notice it anyways
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