What can be measured when no current is flowing in a circuit?

In a circuit where no current is flowing, the open circuit voltage can be measured. Open circuit voltage refers to the potential difference measured across two points in a circuit when there is no load connected and thus no current passing through the circuit. This voltage can be understood as the voltage available from a power source or between two points of a circuit without any influence from devices or components that would otherwise draw current.

Measuring open circuit voltage is essential because it helps in determining whether the power source is functional and at what potential it operates. This measurement is often done with a multimeter or voltmeter connected across the points of interest.

In contrast, short circuit current refers to the maximum current that flows when a circuit path is closed with very low resistance, which cannot be measured when no current flows. Resistance cannot be directly measured without a current influencing the circuit, and while ground potential indicates the voltage level relative to a common reference point, it also requires a flow of current to be accurately interpreted in connection with circuit elements.