Electric current

Electric current:

                Electric current is the flow of electric charge (usually electrons) through a conductor, measured in  Amperes (A) driven by a voltage 

force, and restricted by resistance.

                There are two main types:

1.Direct current (DC),flowing one way (batteries),

2.Alternating current (AC), reversing direction.

Definition:

           The rate of flow of electric charge(q),                       overtime(t) expressed as I=q/t

Charge carriers:electrons in wires ions in,             liquids are both in plasma.

Resistance:Opposition to flow measured in ohms.

Ohms Law:Relates current (I), voltage (v) and       resistance R as I=V/R

Types of current:

 Direct current: electrons flow steadily in one direction.

Alternating current: direction of flow reverses periodically.

 

Analogy : water flow

Voltage (V):water pressure in a pipe (height of a

                    water tank)

Current(I) :the amount of water flowing per                               second flow rate.

Resistance:narrowing of the pipe or a partially

                     Closed tap.