Terminal voltage is the potential difference across the terminals of a battery or power supply when a circuit is connected. It is the actual voltage available to external devices, accounting for internal resistance and load resistance.
5 Must Know Facts For Your Next Test
Terminal voltage decreases as current increases due to internal resistance within the power source.
It can be calculated using the formula $V_{terminal} = E - Ir$, where $E$ is the electromotive force (emf), $I$ is the current, and $r$ is the internal resistance.
When no current flows (open circuit), terminal voltage equals the emf of the battery.
In practical circuits, terminal voltage is always less than or equal to the emf because of energy loss inside the battery.
Understanding terminal voltage helps in designing efficient circuits by ensuring that components receive adequate voltage.
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Related terms
Electromotive Force (emf): The total energy supplied per coulomb of charge by a power source when no current flows.