# Electric Circuits Part 1 Standard Symbols, Electric Current and Quantity of Electricity

An introduction to electric circuits Standard symbols for electrical
components Symbols are used for components and electrical circuit
diagram. Some of the more common ones are conductors, fixed resistors, variable
resistors, cells, battery of cells, switches, filament lamps, fuses ammeters and voltmeters. Electric current and quantity of electricity All atoms consist of protons, neutrons and electrons. The protons, which have positive electrical charges and the neutrons that have no electrical charge are contained within the nucleus. Removed from the nucleus are minute negatively charged particles called electrons. Atoms of different materials differ from one another by having a different numbers of protons, neutrons and electrons When there are more than two
electrons in an atom, the electrons are arranged into shells at various distances
from the nucleus. All atoms are bound together by powerful forces of attraction existing
between the nucleus and its electrons. Electrons in the outer shell of them
however are attracted to their nucleus less powerfully than electrons that are nearer to the nucleus. It is possible for an atom to lose an electron. The atom which is now called
an ion is not now electrically balanced, but is positively charged and is able to
attract electrons from another atom. Such random motion can continue indefinitely However, if an electric pressure or voltage is applied across any material there is a tendency to move in a
particular direction. This movement of free electrons known as drift constitutes an electric current flow. Thus, current is the rate of movement of charge. Conductors are materials that have electrons loosely attached to their atoms Insulators have electrons that are held firmly to their nucleus. The unit used to measure the quantity of electrical charge (Q) is called the Coulomb (C)

## 3 thoughts on “Electric Circuits Part 1 Standard Symbols, Electric Current and Quantity of Electricity”

1. Sailesingh Ramdhony says:

I = 0.06     I =0.042

2. Just Justin says:

6.3 & 40.

3. Gang Gang says:

I= 0.96A
C=2.4kC