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Obtain an expression for the equivalent ...

Obtain an expression for the equivalent emf and internal resistance of two cells connected in parallel.

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Consider m identical cells of emf E and internal resistance connected in parallel across an ecternal resistor of resistance R.

The total in circuit = E ( Since each cell has the same emf and they are in parallel)
The net internal resistance =r/m (since the cells are in parallel, their resistances are also in prallel. If m identical resistances are in parallel, the effective resistance is (r/m)
The total resistance in circuit `= R + r//m`
Therefore, the current in circuit,
Current `= ("Total EMF")/("Total Resistance")`
`I = (E )/( mr + r)`
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