Which instrument measures current?

Which instrument measures current?

• A. Voltmeter
• B. Ohmmeter
• C. Multimeter
• D. Ammeter

Answer: (D)

To measure current, you place the instrument in series with the circuit so that all the current in that path flows through it. The ammeter is designed for this role and has very low internal resistance, so it doesn’t appreciably affect the current it’s measuring and can display the amperage directly. In contrast, a voltmeter is connected in parallel to measure voltage, an ohmmeter measures resistance by applying its own test current, and a multimeter can measure current (along with other quantities) but only when used in its current-measuring mode.

To measure current, you place the instrument in series with the circuit so that all the current in that path flows through it. The ammeter is designed for this role and has very low internal resistance, so it doesn’t appreciably affect the current it’s measuring and can display the amperage directly. In contrast, a voltmeter is connected in parallel to measure voltage, an ohmmeter measures resistance by applying its own test current, and a multimeter can measure current (along with other quantities) but only when used in its current-measuring mode.