Oklahoma Electrical Practice Exam

What device is used for measuring electrical current?

1. Ammeter

2. Voltmeter

3. Wattmeter

4. Ohmmeter

The correct answer is: Ammeter

The device used for measuring electrical current is an ammeter. Ammeter operates on the principle of measuring the flow of electrons (current) through a conductor in a circuit. It is specifically designed to measure current in amperes and can be connected in series with the circuit being tested. This capability is crucial for understanding how much current flows in various components of an electrical system, which can help in troubleshooting or ensuring the system operates within safe limits. The ammeter generally has a low resistance to avoid significantly affecting the current flow in the circuit. In contrast, a voltmeter measures voltage (electrical potential difference) across two points in a circuit and is connected in parallel. A wattmeter is used to measure electrical power in watts, considering both voltage and current, while an ohmmeter measures resistance in ohms by determining how much current will flow through a component in response to a given voltage.