Lesson Notes
- Electric current is the rate of flow of electric charges.
- The standard symbol of current is I.
- The electric charge is denoted by Q, and its SI unit is Coulomb (C).
- The SI unit of current is Ampere and denoted by A.
- The instrument used to measure electric current is called an ammeter.
- The symbol for the ammeter is as follows:
The other units for electric current are:
- Milliamperes (mA): 1mA = $$10^{-3}$$A
- Microamperes ($$\mu$$A): 1$$\mu$$A = $$10^{-6}$$A
- Kiloamperes (kA) : 1kA = $$10^{3}$$
Relationship between charge and electric current
The relationship between charge and electric current is given by the following equation:
$$Q = I \times t$$
where Q is the charge in Coulombs (C), I is the electric current in Amperes (A) and t is time in Seconds (s).