How the numbers on the resistors indicate their size

It is generally a three-digit number, the first two digits are the readings of the resistance, and the last one is how many powers should be multiplied by 10. For example, 124 is 12 times 10, and the power of 4 is 120,000, which is 120k. 223 is 22 times 10 to the power of 3 equals 22000, which is 22k.

The numbers represented by the color of the color wheel are: Brown 1, Red 2, Orange 3, Yellow 4, Green 5, Blue 6, Purple 7, Gray 8, White 9, Black 0

The magnification represented by the color of the color wheel: brown*10, red*100, orange*1k, yellow*10k, green*100k, blue*1m, purple*10m, gray*100m, white*1000m, black*1, gold*silver*

The error level represented by the color of the color ring is: 5% for gold, 10% for silver, 1% for brown, 2% for red, and 20% for green, blue, purple and gray

The reading of the four-ring resistor: the first 2 digits are significant figures, the 3rd digit is the magnification, and the fourth digit is the error level.

For example: brown, red, black, gold 12*1=12 ohms error plus or minus 5%.

Red, red, orange, silver 22*1k=22k error plus or minus 10%.

The reading of the five-ring resistance: the first 3 digits are significant digits, the fourth digit is the magnification, and the fifth digit is the error level.

Brown, red, orange, yellow, green, blue, purple, gray, white, and black respectively represent 1234567890 Gold and silver are 10% allowable deviation, gold 10%, silver 5% Then a resistance has four colors from left to right, the first two digits represent the size of the value, the third digit represents multiplied by 10 to the power of how many powers, and finally the allowable deviation is like brown, violet, yellow, silver is 17 * 10 to the 4th power of the allowable deviation plus or minus 5%.

The unit of resistance is ohms, and the higher the value, the greater the resistance.

Resistance (the magnitude of the conductor's resistance to the current).

Resistance (usually denoted by "R") is a physical quantity that represents the magnitude of a conductor's resistance to an electric current.

The greater the resistance of a conductor, the greater the resistance of the conductor to the current. The resistance of different conductors is generally different, and resistance is a characteristic of the conductor itself. The resistance will cause a change in the flow of electrons, and the smaller the resistance, the greater the flow of electrons, and vice versa.

Whereas, superconductors have no electrical resistance.

The resistance value of the resistive element is generally related to the temperature, material, length, and cross-sectional area, and the physical quantity that measures the influence of the resistance by temperature is the temperature coefficient, which is defined as the percentage of the change in the resistance value for every 1 increase in temperature.

The main physical characteristic of the resistor is that it transforms electrical energy into thermal energy, which can also be said to be an energy-dissipating element, and the internal energy is generated when the current passes through it. Resistors usually play the role of voltage division and shunt in circuits. For signals, both AC and DC signals can pass through resistors.

The resistance of a conductor is usually represented by the letter r, and the unit of resistance is ohm (ohm), referred to as ohm, and the symbol is (Greek letter, pronounced omega), 1 = 1V A. Larger units include kiloohms (k) and megaohms (m) (mega = million, i.e. 1 million).

k (kiloohms), m (megaohms), their conversion relationship is: two resistors in parallel can also be expressed as.

1tω=1000gω；1gω=1000mω；1mω=1000kω；1k = 1000 (i.e. 1,000 advance rate).

Although resistance is defined as: 1 volt voltage produces one ampere of current is 1 ohm resistance; However, voltage and current are not the factors that determine resistance.

The resistance of the resistor is directly proportional to the length of the land noise conductor and inversely proportional to the cross-sectional area.

The factors that determine the magnitude of the resistance are the length of the conductor, the material, the cross-sectional area, and the temperature. Temperature is an external factor, and in common conductors, temperature has little effect on the magnitude of the resistance. Length, material, cross-sectional area are factors of the conductor itself.

Factors that affect the magnitude of the resistance are the material, length, cross-sectional area, and temperature of the conductor. When the material and cross-sectional area are the same, the longer the length of the conductor, the greater the resistance. When the material and length are the same, the smaller the cross-sectional area of the conductor, the greater the resistance.

When the length and cross-sectional area are the same, the conductor resistance of different materials is different. For most conductors, the higher the temperature, the greater the resistance, such as metals, etc.; For a few conductors, the higher the temperature, the lower the resistance, such as carbon.

The resistance of a conductor to an electric current is called the resistance of the conductor. The greater the resistance of a conductor, the greater the resistance of the conductor to the current. The resistance of different conductors is generally different, and resistance is a property of the conductor itself.

The resistance of a conductor is usually represented by the letter r, and the unit of resistance is ohm, referred to as ohm, and the symbol is .

Big, small. The resistance of the conductor is related to its length, material, cross-sectional area and temperature, and the resistance of the conductor is related to the length in the case of the same material and cross-sectional area, and the longer the length, the greater the resistance; In the case of the same material and length, the resistance of the conductor is related to the cross-sectional area, and the larger the cross-sectional area, the smaller the resistance.

Resistivity describes the parameters of the conductivity of a Divine Ruler conductor. For a cylindrical homogeneous conductor made of a certain material, its resistance r is proportional to the free length l and inversely proportional to the cross-sectional area s, i.e., r = l s.

The resistor symbol is .

The resistance of a conductor to the current is called the resistance of the conductor, and the resistance is a physical quantity, which indicates the magnitude of the conductor's resistance to the current in physics.

The greater the resistance of the conductor, the greater the resistance of the conductor to the current. Mu imitates different conductors, and the resistance is generally different, and the resistance is a property of the conductor itself. The resistance of a conductor is usually represented by the letter r, and the unit of resistance is ohms, or ohms for short.

Resistance in the circuit schematic diagram using graphic symbols and letter symbol representation, there is a unified national and international standards, the two are basically the same, there are a variety of drawing methods, should be drawn according to the standard symbols, such as resistance symbols have a variety: ordinary resistance, noisy variable resistor, thermistor, photosensitive chain history resistor, pressure shed touch sensitive resistor, 、......And so on, on the printed board, the size is large or small, there are lead packages, chip packages, and resistor bar packages, which have to be represented according to the graphic symbols of the package library used. It's not simple, it needs to be learned professionally.

Here are just a few of the most commonly used examples:

Resistance is a physical concept, denoted by the symbol r, that refers to the magnitude of a conductor's resistance to an electric current. The magnitude of the resistance is related to the size of the conductor, the material, the temperature. The basic unit of resistance is ohms, referred to as ohms, and the symbol is .

The units with relatively large orange rows include kiloohm (k), megaohms (m), etc., and the conversion relationship is 1t = 1000g; 1gω=1000mω;1mω=1000kω;1kω=1000ω。

Resistors can be used for current limiting, shunting, voltage dividing, converting electrical energy into internal energy, etc.

Resistive Components**Chain Crown Technology Expansion:

Voltage, current, and resistance.

The voltage is U, the current is I, and the resistance is R. According to Ohm's law, the relationship between them is i=u r, i.e., u=ir; r =u/i。

The above is about what the resistor symbol is, I hope it can be helpful to everyone.

Question 1: What factors are related to the magnitude of the resistance Answer: The magnitude of the resistance of a metal conductor is related to the resistivity, length, cross-sectional area, and temperature of the conductor.

According to the law of resistance r= l s

1. The greater the resistivity, the larger the length, the smaller the cross-sectional area, the greater the resistance of the conductor, the higher the temperature increases, the resistivity of the metal conductor increases, and the resistance increases.

2. When the temperature of the conductor drops to a certain temperature, the resistance of the conductor suddenly drops to 0, which is called superconductivity.

3. Thermistile resistance to semiconductors: When the semiconductor is heated, the resistance decreases rapidly with the increase of temperature, and it responds quickly to small temperature changes with high accuracy.

4. For AC circuits, inductance coils, inductance xl=2 fl, capacitance xc=1 2 fc

Question 2: Why is the length of the resistor related to the size of the resistance The relationship between the length of the resistance and the size of the resistance is as follows:

1 It is related to the resistivity of the material. Every type of conductor has its resistivity. The higher the value, the greater the resistance.

2 It is related to the cross-sectional area of the conductor, the smaller the cross-sectional area, the greater the resistance. 3 It is related to the temperature of the conductor, the higher the temperature, the greater the resistance. 4 It is related to the length, the longer the length, the greater the resistance.

The results of the experiments passed: the resistance value of the wire of different materials of the same length and the same cross-sectional area is not equal The cross-sectional area is unchanged, and the resistance value of the wire of the same material is proportional to the length The length is unchanged, and the resistance value of the wire of the same material is inversely proportional to the size of the cross-sectional area.

The law of resistance is summarized: (1) Content: The resistance r of a conductor of the same material is proportional to its length l and inversely proportional to its cross-sectional area s; The conductor electrical group is related to the materials that make it up.

This is the law of resistance. (2) Formula: r=

where l s is the proportionality constant, which is related to the material of the conductor and is a physical quantity that reflects the conductive properties of the material, which is called the resistivity of the material.

Resistance: The resistance of a conductor to an electric current is called resistance.

Magnitude: r=u i r is independent of the voltage u at both ends of the conductor and the current i through the conductor.

Determinant: r = l s resistance r is determined by the material, length, cross-sectional area of the conductor, which is affected by temperature.

The single-phase inlet line shall not be less than 10.

Except for carbon both.

The comprehensive utilization rate of electrical energy is correct, because incandescent lamps convert electrical energy into heat energy (filaments are so hot that they emit light) The heat energy of incandescent lamps can be utilized, and fluorescent lamps are converted into electrical energy and kinetic energy into light energy (electronic friction phosphor, phosphor glows).

1. The concept of resistance.

Resistance: The resistance of a conductor to an electric current is called resistance.

Magnitude: r=u i r is independent of the voltage u at both ends of the conductor and the current i through the conductor.

Determinant: r = l s resistance r is determined by the material, length, cross-sectional area of the conductor.

2. The cross-section of the copper core of the residential entrance line shall not be less than 15 square millimeters. Wrong, there is no 15mm line and there are no specific regulations, it is determined by the size of the load.

3. Copper, aluminum, tin, carbon and mercury are all good conductors. 4. The comprehensive power utilization rate of incandescent lamps is higher than that of energy-saving fluorescent lamps. Mistake.

Resistance: The resistance of a conductor to an electric current is called resistance. Well, yes. It's all a good conductor of electricity. The comprehensive power utilization rate of incandescent lamps is higher than that of energy-saving fluorescent lamps. That's right, but in its main purpose, i.e., luminescence, the utilization rate is not high.

The symbol of the resistor is r, and the unit is ohms.