Finding terminal voltage given two batteries

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To find the terminal voltage in a circuit with two batteries, it's crucial to consider both the external resistance and the internal resistances of the batteries. The formula for terminal voltage is Terminal V = Emf - ir, where 'i' is the current calculated using Kirchhoff's laws. The initial confusion arose from not knowing the internal resistance, but recognizing that the circuit includes two batteries with their respective internal resistances clarified the problem. By factoring in these internal resistances, the terminal voltage can be accurately determined. Understanding the circuit's components is essential for solving such problems effectively.
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Homework Statement


http://www.webassign.net/giancoli5/19_31alt.gif
I was given this circuit and told that R=6.6Ω. Based on the information, I was asked to find the terminal voltage.

Homework Equations


Terminal V=Emf-ir
Kirchoff's laws


The Attempt at a Solution


I used Kirchoff's laws to find i=.61 A. From there, I don't understand how to find terminal voltage without knowing internal resistance. I feel like I wasn't taught an equation or something.
 
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taylorivy said:

Homework Statement


http://www.webassign.net/giancoli5/19_31alt.gif
I was given this circuit and told that R=6.6Ω. Based on the information, I was asked to find the terminal voltage.

Homework Equations


Terminal V=Emf-ir
Kirchoff's laws


The Attempt at a Solution


I used Kirchoff's laws to find i=.61 A. From there, I don't understand how to find terminal voltage without knowing internal resistance. I feel like I wasn't taught an equation or something.

It looks like your circuit shows two batteries each with an internal resistance. So what "terminal voltage" is being referred to?
 
Man, I realized that as soon as I looked at the diagram again. I factored in the two given resistances as the internal ones and it worked out perfectly. Thanks anyway!
 

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