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# AARRGH I am stuck...again watch

1. 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?
2. 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.
3. no its wrong. its an online test and it says its wrong???
4. is anyone there?
5. you fail
6. thanks!!!!
7. (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 *******.
8. great someone agrees with me! Do you have any idea how to do this?!
9. 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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