How does an ohmmeter measure the resistance of a circuit or component?
By applying a small current and measuring the resulting voltage✓Richtige Antwort
By placing a variable resistor in parallel with the circuit
By placing a variable resistor in series with the circuit
By applying a variable voltage and measuring the resulting current change
Erklärung
An ohmmeter has its own internal source: it drives a known small current through the unknown resistance and measures the resulting voltage, and Ohm's law gives R = V / I, which the scale reads out directly. That is why the circuit under test must be unpowered, and why the variable-resistor choices describe something an ohmmeter does not do.