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Hi everybody!
I'm a physicsinterested guy from Norway, who have a question. We don't have any such exellent forums in Norway. :) I hope you understand my english by the way. :)
We have a battery with internal resistance 2 Ohm. The voltmeter shows 9 volt when no current goes through the circuit (switch open). (Then, the electromotive force is 9 volt, right?)
When this switch is closed, i.e. current goes through the circuit, the voltmeter shows 7,8 volt. In this circuit we therefore have a resistance with 13 ohm.
If we now have two resistances (13 ohm and 30 ohm) switched parallell (do you understand my english. :) ). (Then we have a resultant resistance 9,07 ohm, right?)
Then the questions:
1. What shows the voltmeter now? (we need to find the terminal voltage, right?)
2. What's the current through the resistance with 13 ohm?

1. According to my calculations, the terminal voltage now is 7,4 volt.
2. The current through resistance 13 ohm: 0,567 Ampere.
But I don't know whether this is right?
Hope I'll get answer from some physics genius!! :)
I'm a physicsinterested guy from Norway, who have a question. We don't have any such exellent forums in Norway. :) I hope you understand my english by the way. :)
Homework Statement
We have a battery with internal resistance 2 Ohm. The voltmeter shows 9 volt when no current goes through the circuit (switch open). (Then, the electromotive force is 9 volt, right?)
When this switch is closed, i.e. current goes through the circuit, the voltmeter shows 7,8 volt. In this circuit we therefore have a resistance with 13 ohm.
If we now have two resistances (13 ohm and 30 ohm) switched parallell (do you understand my english. :) ). (Then we have a resultant resistance 9,07 ohm, right?)
Then the questions:
1. What shows the voltmeter now? (we need to find the terminal voltage, right?)
2. What's the current through the resistance with 13 ohm?
Homework Equations

The Attempt at a Solution
1. According to my calculations, the terminal voltage now is 7,4 volt.
2. The current through resistance 13 ohm: 0,567 Ampere.
But I don't know whether this is right?
Hope I'll get answer from some physics genius!! :)