776 B
776 B
| categories | tags | |||
|---|---|---|---|---|
|
|
Current
When an appropriate external force is applied, the movement of electrons is from negatively charged atoms (negative ions) to positively charged atoms (positive ions). We call this electrical current.
We use the symbol I to stand for current in equations.
The amount of current is the sum of the charges of the moving electrons past a given point.
Coulombs and amps
We measure charge in Coulombs (C). A Coulomb is an aggregate of the charge of several electrons because their charge is so small: 6.24 \cdot 10 ^{18} electrons.
We measure current in amps. When one coulomb of charge moves past a point in one second it is called an ampere (amp) represented as A.