Understanding Electronic Components: Resistors, Capacitors, and More
Electronic Components
Understanding Electricity: Voltage, Current, Power, and Resistance
Voltage is the potential difference between two points in an electric circuit and the force required to push electrons in a circuit, measured in volts. Current is the flow of electric charge through a circuit, measured in amperes. Power is the rate at which energy is transferred, measured in watts. Resistance is the opposition to the flow of electric current, measured in ohms. Ohm’s law states that the current through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance between them.
Resistors and Capacitors: Main Uses
Resistors are electronic components used to limit the flow of electric current in a circuit. They are commonly used to protect other components from damage due to excessive current and to control voltage levels. Capacitors, on the other hand, are used to store electric charge and energy and to filter or smooth out fluctuations in a circuit’s voltage. They are commonly used in electronic devices such as filters, timing circuits, and power supplies. They allow alternating current to flow and block direct current.
Resistor Color Codes Explained
The color codes on the casing of resistors are used to indicate the value and tolerance of the resistor. The colors are arranged in a specific order, and each color represents a different digit or multiplier. For example, a resistor with brown, black, red, and gold bands would have a value of 1,000 ohms with a tolerance of 5%. The first two colors, brown and black, represent the digits 1 and 0, respectively. The third color, red, represents the multiplier of 100, which gives a total value of 1,000 ohms. The fourth band, gold, represents the tolerance of 5%.
Inductors as Electromagnets
An inductor consists of a long wire wound into a coil. When an electric current is applied, a magnetic field is created. The strength of the magnetic field depends on the material of the coil (more inductance with iron than with plastic), the amount of current (more current equals a stronger magnetic field) flowing, and the number of turns. The higher the number of turns, the stronger the magnetic field.
Transistors: Uses and Main Parts
Transistors are semiconductors. A typical transistor has three leads: the base, collector, and emitter. There are two possible types of transistors depending on the internal configuration of the leads. In NPN configuration, the current flows from the collector to the emitter, and in PNP configuration, from the emitter to the collector. The base controls the flow of current from one lead to another by applying some voltage. This amount of voltage necessary to open the base is called the threshold, which can be different depending on the transistor. Transistors can amplify current, be used as a switch by changing the voltage on the base, and a pair of transistors in push-pull configuration can be used as an oscillator.