JEE Mains · Physics · STD 12 - 3. current electricity
The combination of two identical cells, whether connected in series or parallel combination provides the same current through an external resistance of \(2 \,\Omega\). The value of internal resistance of each cell is ............ \(\Omega\)
- A \(2\)
- B \(4\)
- C \(6\)
- D \(8\)
Answer & Solution
Correct Answer
(A) \(2\)
Step-by-step Solution
Detailed explanation
\(I _{2}=\frac{ E }{\frac{ r }{2}+2}=\frac{2 E }{ r +4}\) \(I _{1}= I _{2}\) \(2 r +2= r +4\) \(2 r - r =2 \,\Omega \Rightarrow r =2 \,\Omega\)
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