Combination of Cells: Parallel Connection

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Two cells with EMFs of 6V and 5V, and internal resistances of 2 ohms and 3 ohms, are connected in parallel without an external load. The terminal potential difference (PD) across any cell is determined to be 5.6V, confirming that option 2 is correct. The discussion clarifies that without an external load, the cells effectively create a closed loop, allowing the same current to flow through each cell. The confusion about the cells being in parallel or series is resolved by understanding that they are parallel with respect to the terminals but in series in the context of the loop. Overall, the participants successfully navigated the problem and confirmed their understanding of the circuit configuration.
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Combination of cells...

Homework Statement


Two cells of emf E1=6V and E2= 5V are joined in parallel with same polarity on same side, without any external load. If their internal resistances are r1=2ohm and r2= 3ohm respectively , then which of the following is true?
1. terminal PD across any cell is less than 5V
2. Terminal PD across any cell is 5.6 V
3. Current through the cell is .2 A
4. current throgh the cells is zero is E1= E2




Homework Equations





The Attempt at a Solution


I got point 2 correct by using the formula for grouping of cells and if 2 is correct one is not...I am ok till that but i am not getting how to do the other parts...(3 nad 4)...what is meant by having no external load and what 'current throgh the cells' are they talking about current through each of them or current through the entire battery(the equivalent cell)?
 
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If there is no load the two cells make a single closed loop and the same current flows through each of them as no current can flow anywhere else.
It is useful if you draw the set-up.

ehild
 


Hi ehild...
There is no diagram given for this question...Now if there is no load(ie as you say same current passes through each cell) then how come they are in parallel...I mean parallel wrt what? If there is no load then they apparently seem to be in series...
 


You should draw a circuit diagram, like the attached one. There are two terminals (A,B) of the "new battery" which can be connected into a circuit or to a voltmeter. With respect to these terminals, A and B, the cells are connected in parallel. With respect to the loop, they are in series.

ehild
 

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Ok...got it...thats how they are parallel...and got the right answers too...thanks...
 
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