What is the term used for the flow of electrons through a circuit?

• A. Voltage
• B. Power
• C. Current
• D. Resistance

Answer: (C)

The flow of electrons through a circuit is current. It measures how much charge passes a point each second, expressed in amperes. In burglar and residential fire alarm systems, current is what carries the signal along the wiring: sensors and devices draw or send current when they change state, and the control panel interprets that flow to trigger alarms or indicate status. Voltage is the push that drives those charges; without a driving voltage, current would be minimal or nonexistent. Resistance is what opposes that flow, determined by the materials and components in the circuit. Power describes how quickly energy is being used or delivered, calculated from the voltage and current. Grasping how current flows and relates to voltage, resistance, and power helps you analyze circuits and troubleshoot alarm systems.