Analysis of important concepts of resistance
In ELECTRONIC CIRCUIT, WHAT USE AMOUNT IS THE BIGGEST IS RESISTOR, APPLICATION SURFACE IS THE WIDEST IS RESISTOR, CHARACTERISTIC IS MOST "PURE" IT IS RESISTOR, CHECK OUT LIULIU2 METHOD THE SIMPLEST ALSO IS RESISTOR, RESISTOR EXISTS NOWHERE IN ELECTRONIC CIRCUIT.
Resistor in the electronic circuit function is quite extensive, it can constitute many multifunctional circuits in the circuit. Resistor in the circuit can not only be used alone, but also in more cases is together with other components to form a circuit with various functions.
The fundamental function of a resistor is to provide a resistance to a circuit. Resistance is a physical quantity.
What is resistance? In general, resistors play the same role in a circuit as resistance in a stream of water.
For the conductor, the existence of resistance makes the current flow encountered resistance, specific performance is the resistance to consume electric energy, obviously in this sense, the role of resistance is deintegrable. However, many specific circuit functions can be achieved by using this characteristic of resistance in circuits.
Resistor is to provide a resistive component for the circuit, resistor by consumption of electricity, distribution of current in the circuit, to achieve a specific purpose.
The relevant knowledge about resistance mainly explains the following points:
(1) Resistance has the size of the division, its unit is ohm, with the letter Q, in addition to ohms and dry (with K ω), megaohm (Mω), the conversion relationship between them is :1k=10002; 1 m Ω = 1000 k.
(2) Another way to express resistance is conductance, which is denoted by G, which is numerically equal to the inverse of resistance, resistance in ohms, conductance in Siemens (ohms).
(3) Generally speaking, objects that can conduct electricity are called conductors, such as the wires used in electric lamps. The resistivity of a conductor is very small, and the resistivity of a conductor of different materials is also different, that is, its conductivity is different, and the resistivity of a superconductor is very small.
(4) An insulator is an object that cannot conduct electricity, such as glass, dry wood, etc. An insulator has a very high resistivity, which is the opposite of a conductor.
(5) The conductivity of semiconductors is between conductors and insulators. Semiconductor materials are widely used in electronic circuits, for example, silicon is a semiconductor material. Active devices such as crystal diodes, triodes and integrated circuits, which can be found everywhere in electronic circuits, are made of this semiconductor material.
(6) In circuit analysis, for the convenience of expression, the resistor is referred to as resistor, such as resistor R1.