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A voltage of 12 V is applied across a circuit with one 3 0hm resistor in series and three 3 Ohm resistors in parallel. What is the total current in the circuit? Select one:a.9 Ampsb.3 Ampsc.6 Ampsd.36 Amps

User Gammer
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1 Answer

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First, let's calculate the equivalent resistance of the three parallel resistors, using the formula below:


\begin{gathered} (1)/(R_(eq))=(1)/(R_1)+(1)/(R_2)+(1)/(R_3)\\ \\ (1)/(R_(eq))=(1)/(3)+(1)/(3)+(1)/(3)\\ \\ (1)/(R_(eq))=1\\ \\ R_(eq)=1\text{ ohm} \end{gathered}

Now, let's add this resistance with the one resistance in series:


\begin{gathered} R_=R_(eq)+R_4\\ \\ R=1+3\\ \\ R=4\text{ ohms} \end{gathered}

To find the total current, let's divide the voltage by the total resistance:


\begin{gathered} I=(V)/(R)\\ \\ I=(12)/(4)\\ \\ I=3\text{ A} \end{gathered}

Therefore the correct option is b.

User Bruno Antunes
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