Two cells in series with internal resistors -- calculate the current

AI Thread Summary
The discussion revolves around calculating current in a circuit with two cells in series, each having internal resistors. Participants emphasize the importance of accurately drawing the circuit and labeling voltages and resistances to apply Ohm's Law (V=IR) effectively. There is confusion regarding the circuit configuration, particularly how the negative and positive terminals of the cells are connected. Clarification is sought on the circuit layout, as discrepancies between the original problem statement and the provided circuit diagram are noted. Accurate representation of the circuit is crucial for solving the problem effectively.
lalallaland
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Homework Statement
A secondary cell having an e.m.f. of 2V and an internal resistance of 1ohm is connected in series with a primary cell having an e.m.f. of 1.5V and an internal resistance of 100ohm the negative terminals of each cell is connected to the positive terminal of the other cell. A voltmeter having a resistance of 50ohm is connected to measure the terminal volatage of the cells. Calculate the voltmeter reading and the current in each cell.

Ans given by book:72.8mA, 34.3mA, 1.93V
Relevant Equations
Kirchhoff law
Can somebody explain this please? I don't understand this.
 
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Welcome to the PF.
lalallaland said:
Can somebody explain this please? I don't understand this.
How about you draw the circuit as described and attach it to a reply? Label the voltages and resistances in the loop, and show us how you can use the equation V=IR to work toward the answer. (We aren't allowed to provide tutorial help here until you show your best efforts). Thanks
 
Hey Berkeman,

Thanks a lot for your answer. I'm really stuck at this problem and it is not leaving my mind. I don't really know how to use V=IR here cause the answer tells me there are two different currents.
 

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lalallaland said:
the answer tells me there are two different currents.
You are given the resistance of the voltmeter. What does that imply?
 
However the circuit you supplied does not match that description.

Could you explain this statement? Because I think my circuit matches the description.
 
If I am reading your circuit correctly, the negative terminal of the 1.5V cell is correctly connected to the positive of the 2V cell. The negative of the 2V cell is connected to ... Where?
 
It's very helpful to actually display text and/or graphics being referred to. Here is the circuit given by OP.
1569731019165.png
 
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