Automotive Electronics Practice Test

The sum of the voltage drops in a series circuit equals the ________.

1. Resistance

2. Source voltage

3. Wattage

4. Amperage

The correct answer is: Source voltage

In a series circuit, the principle that governs the behavior of voltage is based on Kirchhoff's Voltage Law. This law states that the total voltage around a closed circuit loop must equal the sum of the individual voltage drops across each component within that loop. Therefore, the correct answer is that the sum of the voltage drops in a series circuit equals the source voltage. When components such as resistors are connected in series, the voltage drop across each resistor is proportional to its resistance and the current flowing through the circuit. If you were to measure the voltage across each resistor and then add these voltage drops together, the result would be equal to the total voltage supplied by the power source (such as a battery). This relationship is critical in circuit design and analysis, as it allows engineers to predict how voltage is distributed among components, ensuring that each component operates within its specified limits. Understanding this concept is essential for troubleshooting and designing safe and efficient electrical circuits in automotive applications.