Which instrument is used to measure electrical current?

Which instrument is used to measure electrical current?

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

Answer: (A)

To measure current, you need a device that carries the circuit’s current and shows its value. The ammeter is designed for this purpose. It’s placed in series with the circuit so all the current flows through it, and it reads the current in amperes. Because it should hardly affect the circuit, an ammeter has very low resistance. The other meters do different jobs: a voltmeter measures voltage and is connected in parallel with high resistance to avoid drawing current; an ohmmeter measures resistance by applying a small current and reading the response; a multimeter can measure current, voltage, and resistance, but you use the ammeter function for a direct current measurement.

To measure current, you need a device that carries the circuit’s current and shows its value. The ammeter is designed for this purpose. It’s placed in series with the circuit so all the current flows through it, and it reads the current in amperes. Because it should hardly affect the circuit, an ammeter has very low resistance. The other meters do different jobs: a voltmeter measures voltage and is connected in parallel with high resistance to avoid drawing current; an ohmmeter measures resistance by applying a small current and reading the response; a multimeter can measure current, voltage, and resistance, but you use the ammeter function for a direct current measurement.