Question T5A05
From subelement T5 - T5A
What is the electrical term for the force that causes electron flow?
Why is this correct?
Voltage is the electrical force that causes electrons to flow through a circuit, measured in volts (V). Think of it as electrical 'pressure' that pushes electrons from the positive terminal through the circuit to the negative terminal. Ampere-hours measures battery capacity (energy storage), not the driving force. Capacitance measures a component's ability to store electrical charge. Inductance measures opposition to changes in current flow. Only voltage creates the electromotive force needed for electron movement.
Memory tip
Remember 'V for Voltage drives current Velocity' - voltage is always the driving force in electrical circuits. When you see questions about 'force that causes' or 'what drives,' think voltage. Current flows because voltage pushes it, just like water flows because pressure pushes it through pipes.
Learn more
In practical amateur radio operation, understanding voltage as the driving force helps you troubleshoot circuits and design antenna systems. When your handheld radio's battery voltage drops below operating threshold, insufficient electromotive force means weak transmission output. Higher supply voltages in base station transceivers provide the electrical pressure needed to drive higher power amplifier stages, explaining why QRP (low power) operations use lower supply voltages while legal limit amplifiers require much higher DC voltages.
Think about it
Why do you think a 12-volt car battery can start an engine requiring hundreds of amperes, while a 9-volt battery powering a smoke detector cannot, even though both provide electromotive force?