ampere-second
/'æmpeə,sekənd/
Definition
- Noun:
- A unit of electrical charge: An ampere-second is a derived unit of electric charge in the International System of Units (SI). It is defined as the quantity of electric charge transferred by a steady current of one ampere flowing for one second.
Usage
- The ampere-second is the SI unit for electric charge, equivalent to the coulomb (C). It is used to quantify the total amount of electricity that has flowed in a circuit.
- It is commonly used in calculations involving batteries, capacitors, and electrochemistry to describe charge capacity or transfer.
Examples
- Noun:
- The battery has a capacity of 3,600 ampere-seconds. (This means it can deliver a current of one ampere for 3,600 seconds, or one hour.)
- To fully charge the capacitor, you need to supply 0.5 ampere-seconds of charge.
- The total charge moved in the experiment was measured in ampere-seconds.
Advanced Usage
- Scientific Context: In physics and electrical engineering, the ampere-second is a fundamental unit for expressing electric charge (Q), where Q = I × t (charge equals current multiplied by time).
- The law states that the mass of a substance liberated during electrolysis is proportional to the number of ampere-seconds passed.
- Practical Equivalence: One ampere-second is exactly equal to one coulomb. Therefore, the terms are often used interchangeably in technical contexts, though "coulomb" is more common.
- A current of 2 amperes flowing for 5 seconds transfers a charge of 10 ampere-seconds (or 10 coulombs).
Variants and Related Words
- Coulomb (C) (noun): The standard SI unit of electric charge. One coulomb is defined as one ampere-second.
- The charge of an electron is approximately 1.602 × 10⁻¹⁹ coulombs.
- Ampere-hour (Ah) (noun): A larger unit of electric charge, commonly used for batteries. One ampere-hour equals 3,600 ampere-seconds.
- The car battery is rated at 50 ampere-hours.
Synonyms
- Coulomb: The more formal and standard name for the same unit of electric charge.
Related Terms and Concepts
- Electric Current (Ampere, A): The flow of electric charge per unit time. The ampere is the base unit.
- Time (Second, s): The base unit of time in the SI system.
- Faraday Constant: A physical constant representing the charge of one mole of electrons, approximately 96,485 coulombs (or ampere-seconds).
Noun
-
a unit of electrical charge equal to the amount of charge transferred by a current of 1 ampere in 1 second
