Three resistors of \( 2\,\Omega \), \( 2\,\Omega \) and \( 1\,\Omega \) are connected in parallel across a 5 V source. What is the current drawn from the source?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 10 A
Resistors in parallel have the same potential difference across them, and the current drawn from the source is the sum of the branch currents. So the reciprocal of the equivalent resistance is the sum of the reciprocals of the individual resistances.
\( \begin{aligned} \frac{1}{R_{\mathrm{eq}}} &= \frac{1}{2\,\Omega}+\frac{1}{2\,\Omega}+\frac{1}{1\,\Omega} \\ &= 2\,\Omega^{-1} \end{aligned} \)
\( R_{\mathrm{eq}}=0.5\,\Omega \)
The current drawn from the source is:
\( \begin{aligned} I &= \frac{V}{R_{\mathrm{eq}}} \\ &= \frac{5\,\mathrm{V}}{0.5\,\Omega} \\ &= 10\,\mathrm{A} \end{aligned} \)