NICET Fire Alarm Practice Exam

In a series circuit, total resistance is calculated by summing the individual resistances of all components connected in the circuit. This is based on the principle that in a series connection, the current has only one path to follow, and as more resistors (or devices with resistance) are added, the overall opposition to current flow increases.

Each resistor contributes to the total resistance, and since the components are arranged in a straight line, the total resistance is equal to the sum of the individual resistances. Therefore, when additional resistive elements are introduced into the circuit, the total resistance increases. This means that as you add more resistors in series, the total resistance rises, making it more difficult for current to flow through the circuit.

The other options present concepts that do not align with the behavior of series circuits—such as decreasing total resistance, remaining constant, or becoming zero—which are not applicable in this context.