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# Stuck on a EMF question..

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1. Stuck on a EMF question..

I got the wrong answer for part a) in the above question, don't know why though:

Terminal PD = EMF - lost volts

so therefore

Terminal PD = 6 - 0.4 = 5.6

Since V = IR, V/R = I

so 5.6/5.0 = I

I = 28/25 = 1.12 A (not rounded)

but the answer is I = 10/9 = 1.11 A
2. Re: Stuck on a EMF question..
E = IR + Ir
6 = I(5 + 0.4)
I = 10/9 A

"Terminal PD = 6 - 0.4 = 5.6"

That was wrong, you're subtracting the internal resistance from the emf, the "lost volts" is I*r not r
3. Re: Stuck on a EMF question..
(Original post by Antimony)
E = IR + Ir
6 = I(5 + 0.4)
I = 10/9 A

"Terminal PD = 6 - 0.4 = 5.6"

That was wrong, you're subtracting the internal resistance from the emf, the "lost volts" is I*r not r
Oh thank you !

For part b), I just find the PD like one would do normally right? (V=IR)
Last edited by sabre2th1; 17-04-2012 at 19:47.
4. Re: Stuck on a EMF question..
Yep
5. Re: Stuck on a EMF question..
(Original post by Antimony)
Yep
thankss

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Last updated: April 17, 2012
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