Flowing Electricity: Current and Amperes (amps)
Current () is the "flow" of electricity, measured in amperes or "amps" (). One amp is equal to one coulomb () passing a given point in a circuit per second (), or . Coulombs are the standard measure of electrical charge quantity (i.e. electrons or protons).
Current can be derived by Ohm's Law as .
Video: Current (Khan Academy)
Direction of Current
Conventional current is current that "flows" in the direction that the positive charge travels and is usually what's meant when talking about "current" without specifying the type of current. Current flows in the direction that the negative charge travels is usually referred to more explicitly as electron current.
In electrical engineering, contentional current is used for calculations even though currents are typically generated through the flow of electrons rather than protons.
Current can also "flow" in both directions simultaneously, such as in salt water. When salt is dissolved in water it forms free-floating sodium () and chlorine () ions which will both respond to electric force, moving in opposite directions.
Amperes are named after André-Marie Ampèr, known for inventing the solenoid and electric telegraph.
Deeper Knowledge on Current and Amperes
Conductance and Siemens
The ability to conduct to current, measured in siemens
Resistance and Ohms
Opposition to current, measured in ohms
Watt's Law (Power Law)
A formula to define the relationship between power, voltage, and current (P=IV)
A formula for determining voltage, current, and resistance
Broader Topics Related to Current and Amperes
Charge and Coulombs
How force is exerted in electromagnetic field, measured in coulombs
International System of Units (SI)
Formal terms and definitions of the metric system
Build and deconstruct electrically powered devices
Energy that results from charged particles