What device is specifically designed to measure current in a circuit?

• A. Voltmeter
• B. Multimeter
• C. Wire Gauge
• D. Ammeter

Answer: (D)

The device specifically designed to measure current in a circuit is the ammeter. An ammeter is a specialized instrument that provides accurate readings of the flow of electric current, measured in amperes. When connected in series within a circuit, it allows for the measurement of how much current is passing through various components.

In contrast, a voltmeter measures voltage, which is not the same as current. A multimeter can function as both a voltmeter and an ammeter, but its versatility means it is not solely dedicated to current measurement. The wire gauge, on the other hand, is a standard used to determine the thickness of wires, which can affect current capacity but does not measure current itself. Thus, the ammeter is the appropriate choice for measuring electrical current directly in a circuit.