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Questions
Answer the following question.
A cell of emf E and internal resistance r is connected across a variable resistor R. Plot the shape of graphs showing a variation of terminal voltage V with (i) R and (ii) circuit current I.
A cell emf of (E) and internal resistance. (r) is connected across a variable load resistance (R). Draw plots showing the variation of terminal voltage V with (i) R and (ii) the current (I) in the load.
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Solution
Terminal Voltage V can be related to R by the following relation:
(i) `V = (ER)/(R+r)`
⇒ `V = (E)/(1+r/R)`
(ii) Terminal Voltage V can be related to I by the following relation:
V = E - IR
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