Electric Current
Electric current is the flow of electric charge through a material. It is the rate at which electric charge flows past a point in a circuit. The flow of electric charge is typically carried by electrons, which are negatively charged particles.
The SI unit for current is the coulomb per second, or the ampere (A), which is an SI base unit:
1 ampere = 1A = 1 coulomb per second = 1 C/s.
Examples of Electric Currents in Amperes
Here are ten examples of electric currents in amperes, sorted from smallest to largest:
- The current required to light up an LED (Light Emitting Diode) is typically between 10-20 milliamperes (mA).
- The charging current of a small USB-powered device, such as a smartphone, is typically around 1 ampere (A).
- The current flowing through a household light bulb when it is turned on is typically between 0.1 and 1 A.
- The current flowing through a typical laptop charger is around 2-3 A.
- The current required to start a car engine is typically around 50-100 A.
- The current flowing through a household electric stove when all of its heating elements are turned on can range from 20 to 50 A.
- The current flowing through a high-speed train can range from 1,000 to 3,000 A.
- The current flowing through a typical electric car charging station can range from 20 to 400 A, depending on the charging rate.
- The current required to power a small electric motor, such as the ones used in power tools or household appliances, can range from a few amperes to several hundred amperes.
- The current flowing through a typical industrial welding machine can range from 50 to 500 A.
