Combination of cells .

  • #1
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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)?
 

Answers and Replies

  • #2
ehild
Homework Helper
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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
 
  • #3
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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.....
 
  • #4
ehild
Homework Helper
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1,913


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
 

Attachments

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  • #5
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Ok....got it.....thats how they are parallel......and got the right answers too.....thanks....
 

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