Automotive Electronics Practice Test

Which technician is correct regarding the light bulbs wired in series and the effect on voltage drop and current?

1. Technician A only

2. Technician B only

3. Both Technicians A and B

4. Neither Technician A nor B

The correct answer is: Technician B only

When discussing light bulbs wired in series, it is essential to understand how this arrangement affects voltage drop and current. In a series circuit, the total voltage across the circuit is divided among the components connected, which means each light bulb will receive a portion of the total voltage according to its resistance. Since current is the same through all components in a series circuit, this means that the overall current flowing through the circuit will be constant. The current is determined by the total resistance of the circuit and the voltage supplied by the source. If additional light bulbs are added to the series circuit, they increase the total resistance, and as a result, the overall current decreases if the voltage supply remains constant. If Technician B is correct, it suggests that they understand that while the total voltage is divided among the components, the current remains consistent throughout. Therefore, knowing that adding more light bulbs increases resistance and, consequently, decreases the circuit's overall current, is vital for understanding the series circuit behavior. In contrast, if Technician A made statements that were misleading about the behavior of voltage and current in a series circuit, then they wouldn't align with the correct rules of circuit theory. The key point is that the series configuration ensures a specific relationship between voltage, resistance, and current