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Why is connecting in parallel good for creating an EMF? watch

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    if there where many cells in parallel would the current or potential difference increase?
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    (Original post by applestrudle)
    if there where many cells in parallel would the current or potential difference increase?
    It depends on their internal resistances and the external resistance.

    If you're interested I can present more quantitative treatment to your question tomorrow.

    In general, to maximise the voltage across the battery, you have to consider the ratio of internal resistance of each cell and the external resistance r/R. The smaller it is, the more you will want to connect the batteries in series, and the greater it is - the better it is to connect them in parallel (but not purely in parallel - you would make some smaller batteries of cells connected in series, and then connect those batteries in parallel).

    So a strict answer to your question is - most usually not. Connecting cells in series will give better results than in parallel, unless r/R>1, but that would be extremely rare cases.

    Although it also depends on what you're asking about. It's better to connect several cells in parallel than have just one cell, because there is a lower potential drop across the internal resistance as the current that goes through it is only a part of the "total" current. However, usually it's even better to connect those cells in series.
 
 
 
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