Every electric circuit, no matter where it is or how large or little it is, has four fundamental components: an energy source (alternating current or direct current), a conductor (wire), an electrical load (device), and at least one controller (switch). Consider what occurs when you turn on a light in a room. You have just created a circuit between the light fixture and the wall outlet. The circuit can either be completed through the load (in this case, the light bulb) or opened by removing power from it. If the connection is not made, then there is no circuit and the light will not come on.
The conductor is a path that electricity will follow from the energy source to the load. It can be a metal wire inside of a conduit or cable, but it can also be a semiconductor such as a diode or transistor. A capacitor is two sheets of metal with an empty space in between; it is used to store electricity for later use.
Power sources include batteries, generators, and the like. They provide electricity to other devices for useful work. For example, a battery-powered flashlight allows you to see while working on a project around you. Electronic devices such as radios, televisions, and computers require different circuits for operation. These are discussed in detail below.
Electrical loads include appliances such as hair dryers, heaters, and air conditioners. They use electricity to do work such as heat up water or air or run motors.
The circuit may also have other elements added to improve efficiency or change its behavior, such as capacitors to reduce noise or prevent voltage spikes from causing problems further down the line. In reality, any object that produces electricity can be considered part of the circuit, including people.
The power supply is the first line of defense against problems with electricity delivery. It ensures that anything that needs powering up gets done so safely and efficiently. A good power supply should be able to handle the load that it is given and not cause itself problems by overloading. An overload occurs when more current tries to go through a single point than what that point was designed for. This could happen if a lot of heavy equipment is plugged into a wall outlet at once or if several appliances that use a lot of power are turned on at once. Without a protective measure in place, an overloaded circuit could cause your wires to break, which would allow current to flow through other parts of the house or street wiring, possibly causing a fire.
Power supplies come in two basic types: switching and linear.
The Fundamental Elements of an Electric Circuit Every electric circuit, no matter where it is or how large or little it is, has four fundamental components: an energy source (alternating current or direct current), a conductor (wire), an electrical load (device), and at least one controller (switch). The circuit must be complete before it can do any good. If any part of the circuit is broken, then it cannot perform its function.
The circuit must also be capable of delivering a controlled amount of current from the energy source to the load. This is called "control." A circuit that does not deliver a controlled amount of current will cause the device it is connected to to get too hot or burn out prematurely. A switch is used to control the flow of current through the circuit, turning it on and off as needed. Switches come in two main types: mechanical and electronic. A third type of switch is called a "motor starter" and it is used with motors to start them up when electricity is applied to the motor shaft. It works by sending a small current through the rotor of the motor which sets it into motion.
Finally, a battery is an electrochemical cell used to store energy for use by other devices. Batteries come in many different sizes and capacities, but they all work on the same principles. They consist of two electrodes attached to terminals that connect to wires that lead to devices such as radios or lamps.
A basic electric circuit can be made up of a battery (or other energy source), a light bulb (or other energy-consuming device), and conducting wires connecting the two terminals of the battery to the two ends of the light bulb. A simple circuit does not contain any switches or other components that can change the state of the circuit.
In a real circuit, all the parts would be connected together with pins, sockets, cables, etc., but for simplicity's sake we will just connect them directly in series or parallel. The final combination of connections determines what type of circuit we have: direct current (DC) or alternating current (AC). We will discuss both types of circuits below.
The key elements in a circuit are voltage sources and low resistance paths so that the current from each source can reach every part of the circuit. A wire is a very poor conductor compared to copper or aluminum so it is necessary to use connectors at each end of a wire when making a connection. These connectors may be pins or posts on boards or they may be plugs that fit into holes in plates. Either way, they must be fixed to one thing and able to make multiple connections because many wires need to be combined into a single package.
Voltage sources are things that store electrical energy: batteries, power lines, solar panels, and generators are all forms of voltage source.
Every circuit is made up of three primary parts:
A circuit is a closed channel in electronics that permits electricity to flow from one place to another. It may contain numerous electrical components such as transistors, resistors, and capacitors, but the flow is not hampered by a circuit gap or break. A simple circuit is exemplified by a flashlight. The battery provides power to the light bulb which emits light through the casing of the flashlight.
In general, electricity from a source must pass through two circuits before it reaches its destination. One circuit is called the "return path." It returns any electric charge that might have accumulated on something inside the device, back to the source. For example, if the light bulb in the above example burned out, there would be no way for it to remain lit because electricity would not be able to reach it. However, the return path takes care of this problem by including a resistor inside the bulb itself. As long as there is enough resistance between the terminals of the bulb, then electricity will be returned to the source through the same path it came in on. But if the resistance gets too low, then more electricity will be lost than delivered to the light.
The second circuit allows the component to work independently of each other. If the light bulb in the previous example broke, this would not affect the ability of the capacitor to hold an electrical charge.