Nate Core Practice Test

How should a voltmeter be applied to a circuit or load?

1. In series

2. In parallel

3. With a short circuit

4. With a load connected

The correct answer is: In parallel

A voltmeter is designed to measure the potential difference, or voltage, across two points in a circuit. To accomplish this accurately, it must be connected in parallel with the component or section of the circuit where the voltage is being measured. This parallel connection ensures that the voltmeter can provide an accurate reading without significantly affecting the circuit's operation. When a voltmeter is connected in parallel, it takes advantage of the fact that voltage remains the same across parallel components. This ensures the voltmeter measures the correct voltage drop across the component without drawing a substantial amount of current, which could alter the voltage being measured. Connecting a voltmeter in series, on the other hand, would mean that the voltmeter would have to carry the entire circuit current, which could lead to an inaccurate voltage reading and potentially damage the voltmeter if the current is too high. Similarly, connecting it with a short circuit would bypass the component under measurement, making it impossible to measure the desired voltage. Ensuring the load is connected is important for circuit functionality, but on its own does not determine the method of connecting the voltmeter for accurate voltage measurement.