Find EMF of a battery in this circuit

AI Thread Summary
The discussion focuses on simplifying a circuit with two batteries in parallel to find the electromotive force (EMF). Participants express confusion about how to simplify the parallel battery configuration and seek clarification on the process. One user mentions calculating an equivalent resistance of 98.9 and questions its accuracy. The conversation emphasizes using Kirchhoff's Voltage Law (KVL) to determine the unknown EMF when the switch is open. Overall, the thread highlights the importance of circuit simplification for accurate numerical analysis.
jdmaxwell02
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Homework Statement
In the circuit below R=53.0 Ω and assume both batteries have zero internal resistance and the voltmeter and ammeter are ideal. When the switch is open the voltmeter displays 14.2 V.



Find the emf e m f of the unknown battery: ___ V

If the switch is closed what does the ammeter display? ____ A
Relevant Equations
EMF-Ir=IR?
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why did you stop where you did in simplifying the circuit?

EDIT: oh, wait ... I see now. You didn't simplify the circuit at all, you drew the two cases.

Simplify the circuit in each case and you can work it down to numerical answers.
 
phinds said:
why did you stop where you did in simplifying the circuit?

EDIT: oh, wait ... I see now. You didn't simplify the circuit at all, you drew the two cases.

Simplify the circuit in each case and you can work it down to numerical answers.

The two batteries in parallel are kinda confusing me. How would I simplify that? Also, I got 98.9 for the equivalent Resistance. Does that seem correct?
 
jdmaxwell02 said:
The two batteries in parallel are kinda confusing me. How would I simplify that?
First, draw the circuit when the switch is open. With that information, can you find the unknown emf using KVL?
 
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