JEE Mains · Physics · STD 12 - 3. current electricity
Two identical cells each of emf \(1.5\,V\) are connected in series across a \(10\,\Omega\) resistance. An ideal voltmeter connected across \(10\,\Omega\) resistance reads \(1.5\,V\). The internal resistance of each cell is \(......\Omega\).
- A \(5\)
- B \(10\)
- C \(15\)
- D \(20\)
Answer & Solution
Correct Answer
(A) \(5\)
Step-by-step Solution
Detailed explanation
\(V = I \times 10\) \(1.5=\left(\frac{3}{10+2 r }\right) \times 10\) \(r =5\,\Omega\)
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