Ampere
The SI base unit of electric current, defined by fixing the elementary charge to e = 1.602176634 × 10⁻¹⁹ C.
Governing formula
1 A = 1 C / s
SI unit
A
In depth
One Ampere represents the passage of 6.241509 × 10¹⁸ elementary charges per second through a conductor cross-section.
Examples in the real world
A typical smartphone charger draws ~1 to 2 Amperes of DC current, whereas a household circuit breaker trips at 15 to 20 Amperes.