The capacity of a battery is expressed in terms of which of the following?

The capacity of a battery is expressed in ampere-hours (Ah). This unit indicates how much current a battery can deliver for a specified period of time. For instance, a battery rated at 10 ampere-hours can theoretically provide a consistent current of 10 amps for one hour, or 5 amps for two hours, and so on, until it is fully discharged.

Other units like watt-hours relate to the total energy a battery can deliver, but they incorporate voltage and are not a direct indication of battery capacity in terms of current. Similarly, amperes measure the flow of electric current at a specific moment and do not account for time. Watts represent the power being used at a given moment but also don’t address overall battery capacity directly. Ampere-hours remains the standard measurement for expressing how much sustained current a battery can supply over time, making it the correct choice for this question.