True or false: A voltmeter is connected in parallel to measure voltage across a component.

True or false: A voltmeter is connected in parallel to measure voltage across a component.

• A. True
• B. False
• C. It depends on the circuit
• D. It measures current when in parallel

Answer: (B)

To measure voltage across a component, you place the voltmeter in parallel with that component. A voltmeter reads the potential difference between two points, so connecting it across the component ensures it sees the same voltage as across those points. Its high input resistance minimizes current drawn from the circuit, so the measurement does not noticeably disturb the circuit’s operation. If the voltmeter were placed in series, it would affect the current through the circuit and would not reliably indicate the voltage across the component. Devices used to measure current are placed in series as ammeters, and they have low resistance to avoid dropping voltage. So the statement is true.

To measure voltage across a component, you place the voltmeter in parallel with that component. A voltmeter reads the potential difference between two points, so connecting it across the component ensures it sees the same voltage as across those points. Its high input resistance minimizes current drawn from the circuit, so the measurement does not noticeably disturb the circuit’s operation. If the voltmeter were placed in series, it would affect the current through the circuit and would not reliably indicate the voltage across the component. Devices used to measure current are placed in series as ammeters, and they have low resistance to avoid dropping voltage. So the statement is true.