Current is measured in ______.

• A. Amperes
• B. Volts
• C. Watts
• D. Ohms

Answer: (A)

Current is the rate at which electric charge flows through a conductor. The unit for this flow is the ampere (A), defined as one coulomb of charge passing a point each second. In automotive contexts, amperes tell you how much current is drawn or supplied by components like lights, starters, and the alternator, and fuses are rated in amperes to protect circuits. Voltage, the potential difference driving the flow, is measured in volts; power is the product of voltage and current and is measured in watts; resistance, which opposes current, is measured in ohms. Ohm’s Law ties these together: current equals voltage divided by resistance. For example, with 12 V across a 6-ohm load, the current would be 2 A.