NEIEP Mechanics Practice Exam

What must be done when testing resistance to avoid false readings caused by parallel circuit paths?

1. Change the setting on the multimeter

2. Remove one of the two wires to the item being tested

3. Use a higher voltage supply

4. Clamp the connections tight

The correct answer is: Remove one of the two wires to the item being tested

When testing resistance in a circuit, it is important to avoid false readings that can occur due to parallel circuit paths because these paths can create alternate routes for the current and lead to misleading measurements. To ensure accurate resistance measurements, removing one of the two wires to the item being tested ensures that the component is isolated from the rest of the circuit. This isolation prevents any additional paths for current to flow, allowing the multimeter to provide a reading that reflects only the resistance of the component being investigated. When the component is disconnected from any parallel paths, the multimeter can apply its own small test voltage and measure how much current flows through the component, providing a true resistance reading. Keeping the circuit intact could lead to a situation where other components influence the measurement due to their parallel connections. The other responses don’t effectively address the issue of parallel paths creating false readings. Setting adjustments on a multimeter or using a higher voltage supply do not eliminate the influence of parallel pathways. Additionally, clamping connections tight ensures good contact but does not prevent unintended current paths from affecting the resistance measurement.