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    Hi there everyone,

    I got a really troublesome question that i need help with, here's how it goes:

    "A car battery with a 14.2 V emf and an internal resistance of 0.0500 ohms is being charged with a current of 70.0 A.

    What is the potential difference across its terminals?"

    I used V=e(emf)-Ir and got 10.7 which is wrong! I now have no idea how to complete the question, any ideas?
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    Equation is OK.

    emf = 14.2 - (0.05 x 70)
    = 14.2 - 3.5
    = 10.7 v

    Either the data given is wrong - or the answer in the book is wrong.
    • Thread Starter
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    no its wrong. its an online test and it says its wrong???
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    is anyone there?
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    you fail
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    thanks!!!!
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    (Original post by kklol)
    you fail
    If you're not going to help then don't bother posting. Judging by your copious neg rep I'd say you're just naturally an *******.
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    great someone agrees with me! Do you have any idea how to do this?!
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    could the answer be more simple than i first thought?

    Could i use V=IR and make V=70x.05 = 3.5v? then 14.2-3.5= oh...10.7v.
 
 
 
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