A voltmeter connected across two points in a circuit measures which quantity?

A voltmeter connected across two points in a circuit measures which quantity?

• A. Current
• B. Power
• C. Voltage
• D. Resistance

Answer: (C)

Voltage is the potential difference between two points, and a voltmeter is placed across those two points to sense that difference. By connecting across two points, the meter reads the energy per unit charge that would move from one point to the other, which is precisely the voltage between them. The meter is designed with very high input resistance, so it draws only a tiny current and doesn’t disturb the circuit. The reading you see is in volts and reflects that potential difference. This isn’t a device that directly measures current—that would require an ammeter in series. It also doesn’t directly measure resistance—that’s what an ohmmeter does. And it doesn’t measure power on its own unless you combine the voltage reading with a current reading or use a wattmeter. In AC circuits, some voltmeters can show RMS voltage if equipped for that, but the core idea remains: it measures the voltage difference between two points.

Voltage is the potential difference between two points, and a voltmeter is placed across those two points to sense that difference. By connecting across two points, the meter reads the energy per unit charge that would move from one point to the other, which is precisely the voltage between them. The meter is designed with very high input resistance, so it draws only a tiny current and doesn’t disturb the circuit. The reading you see is in volts and reflects that potential difference.

This isn’t a device that directly measures current—that would require an ammeter in series. It also doesn’t directly measure resistance—that’s what an ohmmeter does. And it doesn’t measure power on its own unless you combine the voltage reading with a current reading or use a wattmeter. In AC circuits, some voltmeters can show RMS voltage if equipped for that, but the core idea remains: it measures the voltage difference between two points.