The rate of flow of charge, I=dQ/dt, measured in amperes.
Current I=dQ/dt is the rate of flow of charge. Conventional current flows from positive to negative, opposite to electron motion. DC flows one way, AC alternates. Current is measured in series with an ammeter.
A phone charger delivering 2 A moves 2 C of charge each second.
Current is what delivers energy to a load and what heats wires, so it sets conductor size, fuse rating and battery capacity.
The rate of flow of charge, I=dQ/dt, measured in amperes.
Current is what delivers energy to a load and what heats wires, so it sets conductor size, fuse rating and battery capacity.
Conventional current is the flow of positive charge, which is the direction used in circuit analysis. Electrons move in the opposite direction.
An ampere is one coulomb per second, a practical unit defined by the force between two current-carrying wires.
Typical applications include choosing the wire gauge for a 20 A circuit, measuring the draw of a battery-powered sensor over time and checking the current taken by a motor during start-up.
Study "Electric charge" first (topic 1 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
1 A = 1 C/s. Current is the same through series elements. Current density J=I/A.
A phone charger delivering 2 A moves 2 C of charge each second.
The next topic is "Voltage", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 2 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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