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Question
A resistor R is connected to a cell of-emf e and internal resistance r. The potential difference across the resistor R is found to be V. State the relation between e, V, Rand r.
Solution
e = IR + Ir
Where E is EMF of the cell
V = IR is potential drop across external; resistance R.
Ir is potential drop across internal resistance r.
e = V + Ir
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