JEE Mains · Physics · STD 12 - Current electricity
- JEE Mains 2019
- Medium
- Numerical
When the switch \(S\), in the circuit shown, is closed, then the value of current \(i\) will be ................. \(A\)

Pick an option to check your answer.
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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