In electric circuit, the energy carriers are free electrons.
COULOMB – basic unit of electric charge
***To produce 1 coulomb of electric charge, 6.3 x 10 by 18 electrons are required.
ELECTRIC CURRENT
When charges move in a material, current is
produced. The current tells the rate of flow of
charges in it,
Current (I) = amount of charge (Q)
Time (t)
Ampere (A) – unit of current
1 A = 1 Coulomb per second (C/s)
***If the current in an electric circuit says 5 A,
there are 5 C of charge that flow past a point in one second.
1 ampere = there are 6.3 x
10^18 electrons (1 Coulomb)
passing a cross section in 1 second
If current through a flashlight bulb is 0.3 A, how many
electrons will pass at any point in the flashlight circuit
every second?
1 a = 1C/ sec
= 0.3 A/sec x sec / 6.3 x 10^18 C
= 0.048 A
C= It= (0.048 C/sec) (1 sec) = 0.048 C
AC ( alternating current)
DC (Direct current)
Types of Current
What is Direct Current?A battery
produces direct current
in a circuit because the
terminals have the
same opposite charges.
A kind of current in household
circuits wherein there is a
continuous back and forth
movement of electrons in the
circuit.
What is alternating current?
Direct Current
DC Provided by batteries
Alternating Current
AC Provided by power companies