Question

Difficulty: EasySeries Circuits

An auxiliary automotive circuit connects a 12 V12\ \text{V} direct current (DC) power source in series with two resistors valued at 2 Ω2\ \Omega and 4 Ω4\ \Omega. What is the total current flowing through the circuit?

  1. 2 A2\ \text{A}Answer
  2. B
    9 A9\ \text{A}
  3. C
    0.5 A0.5\ \text{A}
  4. D
    72 A72\ \text{A}

Answer

The total current flowing through the circuit is 2 A2\ \text{A}.
In a series circuit, total resistance is the direct sum of the individual resistors: RT=2 Ω+4 Ω=6 ΩR_T = 2\ \Omega + 4\ \Omega = 6\ \Omega. Using Ohm's law (I=V/RTI = V / R_T), dividing the source voltage of 12 V12\ \text{V} by the total resistance of 6 Ω6\ \Omega yields a total current of 2 A2\ \text{A}.

Step-by-Step Solution

1
Calculate the total equivalent resistance (RTR_T) of the series circuit.
RT=R1+R2=2 Ω+4 Ω=6 ΩR_T = R_1 + R_2 = 2\ \Omega + 4\ \Omega = 6\ \Omega
In a series circuit, total resistance equals the sum of all individual resistances.
2
Calculate the total circuit current (II) using Ohm's law.
I=VTRT=12 V6 Ω=2 AI = \frac{V_T}{R_T} = \frac{12\ \text{V}}{6\ \Omega} = 2\ \text{A}
Ohm's law states that current equals voltage divided by total resistance.

Key Concept

Series Circuit Resistance and Ohm's Law
Estimated Time:45s
Rate this question