JEE Mains · Physics · STD 12 - 3. current electricity
When the switch \(S\), in the circuit shown, is closed, then the value of current \(i\) will be ................. \(A\)
- A \(3\)
- B \(5\)
- C \(4\)
- D \(2\)
Answer & Solution
Correct Answer
(B) \(5\)
Step-by-step Solution
Detailed explanation
\( \mathrm{i}_{3}+\mathrm{i}_{2} =\mathrm{i}_{1} \) \( \frac{20-\mathrm{v}}{2} +\frac{10-\mathrm{v}}{4}=\frac{\mathrm{v}}{2} \) \( \mathrm{v}=10 \,\mathrm{V} \) \(\Rightarrow \quad \mathrm{i}_{1} =\frac{10}{2} \) \(=5 \,\mathrm{amp} \)
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