Thus far, this particular unit of The Physics Classroom tutorial includes focused on the essential elements of an electric circuit and upon the notions of electric potential difference, current and resistance. Conceptual meaning of terms have been introduced and applied to simple circuits. Mathematical relationships between electrical quantities are discussed along with their use in resolving issues has been mimicked. Lesson 4 will concentrate on the means by which two or more electric apparatus can be joined to form an electric circuit. Our conversation will progress from simple circuits to mildly complex circuits. Former principles of electric potential difference, current and resistance will be applied to those complex circuits and the exact mathematical formulas are used to examine them.
Description with Words: Three D-cells are set in a battery pack to power a circuit comprising three bulbs. Employing the verbal explanation, one may acquire a mental image of the circuit being described. However, this time, the relations with light bulbs is accomplished in a way such that there's a point on the circuit where the cables branch away from each other. The branching location is known as a node. Every light bulb is placed in its own branch. These branch wires finally connect to each other to make another node. A single cable is used to connect this second node into the negative terminal of the battery.
Electric circuits, whether simple or complicated, can be clarified in various ways. An electric circuit is commonly explained with mere words. Saying something like"A light bulb is connected to some D-cell" is really a decent amount of words to describe a simple circuit. On many occasions in Lessons 1 through 3, words are used to spell out circuits. Upon hearing (or reading) the words, a person develops accustomed to immediately picturing the circuit in their thoughts. But another way of describing a circuit is to draw it. Such drawings offer a faster mental picture of the real circuit. Circuit drawings like the one below have been used several times in Lessons 1 through 3.
A single cell or other power supply is represented by a long and a short parallel line. An assortment of cells battery has been represented by a collection of long and short parallel lines. In both situations, the long point is representative of the positive terminal of the energy supply and the short line signifies the negative terminal. A direct line is utilized to represent a linking cable between any two components of this circuit. An electrical device that offers resistance to this flow of charge is generically known as a resistor and is represented by a zigzag line. An open button is generally represented by offering a rest in a direct line by lifting a portion of the line upward in a diagonal. These circuit symbols are frequently used throughout the rest of Lesson 4 as electric circuits are represented by assessing diagrams. It will be very important to memorize these symbols or to consult with this short list often until you are accustomed to their use.
The above circuits believed that the 3 light bulbs were attached in such a way that the rate moves through the circuit could pass through each one of the three light bulbs in sequential manner. The path of a positive test charge leaving the positive terminal of the battery along with traversing the circuit would involve a passage through every one of the three joined light bulbs prior to returning to the negative terminal of the battery. But is this the sole way that three light bulbs could be joined? Do they have to get connected in consecutive fashion as shown previously? Absolutely not! In reality, instance 2 below contains the same verbal description with the drawing as well as the schematic diagrams being drawn differently.
Description with expressions: 3 D-cells are placed in a battery pack to power a circuit comprising three bulbs. Using the verbal explanation, an individual can acquire a psychological picture of this circuit being clarified. This informative article can then be represented by a drawing of 3 cells and three light bulbs attached by wires. The circuit logos can be utilized to represent the same circuit. Note three sets of long and short parallel lines are utilized to symbolize the battery pack with its three D-cells. And note that every light bulb is symbolized by its own individual resistor logo. Straight lines have been utilized to link both terminals of the battery to the resistors and the resistors to each other.
A final method of describing an electrical circuit is by use of traditional circuit symbols to offer a schematic structure of the circuit and its components. Some circuit symbols used in schematic diagrams are displayed below.
Both of these examples illustrate both common types of connections made in electric circuits. When a couple of resistors are present in a circuit, they may be linked in series or in parallel. The remainder of Lesson 4 will be devoted to a report on these two kinds of connections and also the impact that they have upon electrical quantities such as current, resistance and electric potential. The next part of Lesson 4 can introduce the distinction between series and parallel connections.