An electrical circuit is often described with words. On many occasions in Lessons 1 words have been used to describe simple circuits. But another means of describing a circuit is to draw it. Such drawings offer a quicker mental snapshot of the true circuit. Circuit drawings like the one below are used many times in Class 1 through 3.
Employing the verbal description, one can get a psychological picture of the circuit being clarified. This verbal description can then be represented by a drawing of three cells and three light bulbs attached by cables. The circuit logos can be employed to represent exactly the same circuit. Be aware that three sets of short and long parallel lines are utilized to symbolize the battery pack with its own three D-cells. And note that each light bulb is symbolized with its own individual resistor logo. Straight lines are utilized to connect the two terminals of the battery to the resistors and the resistors to one another.
Thus far, this unit of The Physics Classroom tutorial has concentrated on the crucial elements of an electric circuit and upon the notions of electric potential difference, resistance and current. Conceptual meaning of phrases have been introduced and applied to simple circuits. Mathematical connections between electrical quantities have been discussed along with their use in solving problems has been mimicked. Lesson 4 will concentrate on the means by which a couple of electric devices can be connected to form an electric circuit. Our discussion will progress from simple circuits into mildly complex circuits. Former principles of electrical potential difference, current and resistance will be applied to these complex circuits and exactly the same mathematical formulas are used to examine them.
A single cell or other power source is represented with a long and a brief parallel line. A collection of cells battery is represented by a collection of short and long parallel lines. In both situations, the long point is representative of the positive terminal of the energy supply and the short line signifies the terminal. A straight line is utilized to symbolize a connecting wire between any two elements of the circuit. An electric device that delivers resistance to the flow of control is generically referred to as a resistor and can be symbolized by a zigzag line. An open switch is generally represented by supplying a break in a straight line by lifting some of the line upward at a diagonal. These circuit logos are frequently used throughout the rest of Lesson 4 as electrical circuits have been represented by assessing diagrams. It will be important to either memorize those symbols or to consult with this short list often till you become accustomed to their usage.
Both of these examples illustrate both common kinds of connections made in electric circuits. When two or more resistors exist in a circuit, then they can be linked in series or in parallel. The rest of Lesson 4 will be dedicated to a report on both of these different types of connections and the impact they have upon electrical quantities such as current, resistance and electrical potential. The next portion of Lesson 4 can introduce the distinction between parallel and series connections.
A final way of describing an electrical circuit is by use of traditional circuit logos to provide a schematic diagram of this circuit and its elements.
Employing the verbal description, one can acquire a mental image of the circuit being clarified. But this moment, the relations with light bulbs is achieved in a manner such that there's a stage on the circuit where the wires branch off from every other. The branching location is known as a node. Every bulb is placed in its own division. A single cable is used to connect this second node into the negative terminal of the battery.
The aforementioned circuits assumed that the three light bulbs were connected in such a manner in which the price moves through the circuit would pass through each one of the 3 light bulbs in consecutive fashion. The course of a positive test rate departing the positive terminal of the battery and also traversing the external circuit would demand a passing through each one of the 3 connected lighting bulbs prior to returning into the negative terminal of the battery. However, is this the sole way that the three light bulbs could be linked? Do they have to be connected in consecutive fashion as shown above? Surely not! In actuality, illustration 2 below includes the exact verbal description with the drawing along with the schematic diagrams being drawn otherwise.