How does electricity work?

When a load, such as a light bulb, is connected to a battery, the flow of current always travels from negative to positive terminals. Because is flowing in only one direction ands is flowing at an unfluctuating and steady rate, it is called regular direct current. We'll describe later how other types of current are produced. The flow of regular direct current can be compared with the flow movement of water in a piped system can also be applied to the movement of electrons in an electric circuit. They are pressure, quantity rate flow and resistance.

Pressure is the force that moves water through pipes it is also the force that moves electrons through conductors. Just as the pump produces water pressure, The battery produces electric pressure. Quantity is one case the amount of water moved by the pump, and in the other amount of electrons moved by the battery.

Rate of flow is speed or the strength of flow of water through the pipes and of electrons through the conductors, Resistance is the opposition produced by the pipes and fittings to the flow of water as well as the opposition produced by the conductors to the flow of electrons. Just as the pump must produce a sufficient pressure to overcome the resistance in order to move a unit quantity of water thru a pipe, so must the battery produce a sufficient pressure to move a unit quantity of electrons through a conductor.

While the terms electromotive force, or voltage and potential difference are closely related and are often used interchangeably, there are technical differences among them. In brief, emf , or voltage, is the pressure produced brought and electric circuit, while potential difference indicated the ratio of electro potency or concentration between the electrode of a battery between certain components of other current-produced devices.

Just as units of measure have been established to measure the quantity of liquid, so have units been established to measure the quantity of electricity. When we deal with larger quantities of water, we use the term gallon. A gallon is a 4 quarts, or 8 pints, or 128 ounces. While the electron can be considered to be a quantity of electricity, it is too small to be used as a standard of measure. A larger unit, comprising 6.3 billion billion of electrons, is called a coulomb © and is the standard unit of quantity measure. The unit is names for Charles Coulomb, a French physicist, who made investigations into magnetism and electricity. Although the coulomb is a definite quantity of electrons which can be measured in a laboratory, it is of little concern to us from a practical standpoint.

Coulombs alone can no more measure the strength of an electric current than the gallon alone can measure the strength of a waterfall. Both must be considered in their relation to time. If we say that Niagara Falls spills 5 million gallons of water, it means very little unless the time required for this amount of spill is also given. If it takes a year to spill this amount, it would not be much of a waterfall. However, if it is known that it takes only an hour, from this its strength can be determined. The rate of flow of electrons is measured in amperes.