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What do the poles and zeros of a filter mean
The filter can be regarded as a system of signal processing, and there is a certain relationship between its input and output. This relationship can be expressed by mathematical expression in both time domain and frequency domain. The mathematical expression is the expression of the numerator and denominator which are polynomials (called transfer function), so that the zero point makes the numerator of the transfer function zero, The pole satisfies the condition that the denominator of the transfer function is zero
Personal opinion, for reference only!
What is the physical meaning of the zero angle frequency and the pole angle frequency of the network frequency response function!
It's best to use specific symbols and equations.
The zeros affect the phase frequency response and the poles affect the amplitude frequency response
When an ammeter is used with a current transformer, it is fixed at five amperes. How is the ratio calculated?
I want to know, for example, how to calculate a 20:5 current transformer? Does he mean that if the meter goes 2 degrees, then the time is 2 times 20 degrees?
20:5 means that the conversion ratio is 20 / 5 = 4. Connect it to the 5A watt hour meter. If the running index of the watt hour meter is 1, then the actual degree of the watt hour meter is 1 * 4 = 4
A specification for the "220 V, 2000 W" furnace, the circuit in the normal work of the resistance
If the grid voltage is 200V, calculate the actual power of the circuit. Under the voltage of 200V, if the furnace is used for an average of 2 hours per day, how many kwh of electricity does the furnace consume in a month? (a month = 30 days)
I=P/U 2000W/220V=9.1A R=U/I 220V/9.1A=24.2Ω
I=U/R 200V/24.2Ω=8.25A P=UI 200x8.25A=1650W
1650Wx2=3.3KW/H 3.3KW/Hx30=99KW/H.
Resistance in normal operation: 24.2 Ω
Voltage: 200V, actual power: 1.65kw
Using the electric furnace for 2 hours a day and consuming 99 kW / h per month
If a bulb marked with "220 V 40 W" is connected to a 110 V circuit, what is the actual power of the bulb?
Resistance R = 220 ^ 2 / 40
Connect it to a 110V circuit, and the actual power of the bulb is p = 110 ^ 2 / r = 10W
Find the wiring diagram of three current transformers, three ammeters and one three-phase four wire watt hour meter
Thank you
Connect the ammeter in series between the watt hour meter and the transformer. Transformer - ammeter in - ammeter out - watt hour meter in - watt hour meter out - transformer. Connect the three phases in the same way. Remember: do not connect in parallel. In this way, the current will be divided, resulting in inaccurate measurement
Do 100 ohm resistors have different power? How to distinguish them?
I only know how many ohms of resistance to use. But what is power and how to choose it?
What is the difference between a 100 ohm resistance connected to a 3V battery and a 100 ohm resistance connected to a 220V battery?
Of course, there is a distinction between power. The simplest way is to look at the size and volume of the resistance. The larger the volume of the resistance, the greater the power. The choice of power depends on the consumption of the resistance in the circuit. For example, if the voltage at both ends of the circuit is 1V and the current is 1a, then you need to choose a resistance of more than 1W, not less than 1W
Big power makes big volume. Generally, 1 / 16 or 1 / 8W is enough for radio and stereo. Because the volume is very small, it is not marked. Large wattage, large volume, marked.
Calculate the voltage, and then calculate the power P
Generally, the power of small resistance is 1 / 16W, 1 / 8W, 1 / 4W, 1 / 2W, 1W, 2W, 3W. It won't be marked. Generally, it's about 1W! Larger ones, there will be labels, and there will be heat sinks on high-power resistors
Explain it when you buy it. General radio, computer and other circuits are 5V, the highest 12V voltage, do not need to connect high-power resistor
And then calculate the power
Generally, the power of small resistance is 1 / 16W, 1 / 8W, 1 / 4W, 1 / 2W, 1W, 2W, 3W. It won't be marked. Generally, it's about 1W! Larger ones, there will be labels, and there will be heat sinks on high-power resistors
Explain it when you buy it. General radio, computer and other circuits are 5V, the highest 12V voltage, do not need to connect high-power resistor
It is known that the resistance of the electric furnace r = 20 ohm. Connect it to the 220 V power supply and use 2 small things to calculate the power consumption of the electric furnace
Electric furnace is pure resistance, w = (u ^ 2 / R) * t = (220 ^ 2 / 20) * 2H = 4.84kwh, that is 4.84kwh
The power consumption of a 220 V 40 W bulb connected to a 110 V circuit is 100%
The power consumption is 20W. Because the voltage is reduced by half and the resistance is unchanged, the work is reduced by half
How to read the watt hour of dts8666 three-phase four wire watt hour meter with current transformer of 50 / 5
Three 50 / 5 current transformers are used. How to read the electric degree?
The power on the meter * 10 times!
The quantity of electricity displayed by the meter multiplied by the transformer ratio:
Display power multiplied by 10
RELATED INFORMATIONS
- 1. What can an ammeter measure besides the current?
- 2. In the circuit shown in the figure, both ammeter and voltmeter are ideal ammeter. If resistance R1 is open circuit, the following statements are correct () A. The current indicates that the number becomes smaller; B. the voltage indicates that the number becomes larger; C. the power consumed by R3 becomes larger; D. the power consumed by the circuit in the power supply becomes larger
- 3. Measure the resistance with missing meter method, from the positive pole to the resistance RO and then to Rx, ammeter, switch to the negative pole, RX and RO are connected in parallel, and Rx resistance value is calculated with known power supply voltage ro resistance value
- 4. If the indication of the ammeter increases by 4 times, R? Ohm resistance should be given Such as the title Better have an explanation
- 5. As shown in the figure, given the resistance R1 = 3 Ω, R2 = 6 Ω, the indication of ammeter A is 0.6A, then the indication of ammeter A1 is 0.6A______ .
- 6. A circuit composed of a resistor, a power supply and an ammeter in series, The indication of the ammeter is 0.12A; if a 10 ohm resistor is connected in series in this circuit, the indication of the ammeter is 0.1A. Calculate the voltage of the power supply and the resistance in the original circuit
- 7. In the circuit shown in the figure, the power supply voltage remains unchanged, R1 = 10 Ω. When the switch S is closed and the slide P of the sliding rheostat is in the middle point, the indication of the ammeter is 0.3A; when the slide P is moved to the rightmost end, the indication of the ammeter is 0.2A. Then the power supply voltage is 0.3A______ 5. The maximum resistance of sliding rheostat is______ Ω．
- 8. If the internal resistance Ra of the ammeter is 0.03 ohm and the internal resistance RV of the voltmeter is 2 kiloohm, the resistance R to be measured is about 1.5 kiloohm, and the internal and external connection methods have small error
- 9. The internal resistances of small range ammeter g, ammeter A and voltmeter V are RG, RA and RV respectively A. RG＜RA＜RVB. RV＜RA＜RGC. RA＜RG＜RVD. RG＞RV＞RA
- 10. The voltage at both ends of a conductor is 12 volts, and the current intensity passing through it is 0.9 amperes, so that the current intensity passing through it is 0.6 amperes, and the voltage applied at both ends of it should be more than 10 amperes
- 11. The physical layer is the foundation of all networks. How many volts are used to represent 1, how many volts are used to represent 0, and how long does a bit last for microseconds?
- 12. What do electric fish and volt battery mean
- 13. In the study of microscopic particles, electron volt (EV) is often used as the unit of energy. 1eV is equal to the kinetic energy of an electron accelerated by 1V voltage. Please deduce the conversion relationship between electron volt and Joule
- 14. In the motor model, the coil resistance is 1 ohm, the voltage at both ends is u = 2 V, and the current in normal operation is 0.8 ampere 1. Electric energy consumed in 1min when small motor works normally 2. The internal energy produced in 1min when the small motor works normally? 3. The mechanical energy produced in 1min when the small motor works normally? 4. Heating power of small motor in normal operation? 5. Total power of small motor in normal operation? 6. Output power of small motor in normal operation?
- 15. When the coil resistance of a motor is 1 ohm, the voltage applied at both ends of the coil is 2V, and the current is 0.8A, the electric energy consumed by the motor in normal operation for one minute is____ J, What is the converted mechanical energy J
- 16. When a motor works normally, the coil voltage is 220V, the coil resistance is 2 ohm, the current is 10a1s, the electric energy consumed is j, and the heat generated in 1min is J
- 17. The resistance of a motor coil is 1 ohm, When the voltage applied at both ends of the coil is 2V, the current is 0.8A, and the motor works normally. Calculate the electric energy consumed by the motor in normal operation for 1min The second question is how much mechanical energy is converted by the motor working for one minute?
- 18. How many joules is one degree of electricity
- 19. Physics of senior two! In the chapter of electromagnetic induction, we need to find Joule heat and use the conservation of energy. Why not calculate the work done by Ampere force?
- 20. In electromagnetic induction, is Joule heat transformed from the work done by Ampere force? In other words, in terms of energy conservation, the work done by Ampere force [assuming no friction] is equal to the kinetic energy obtained by conductor rod and Joule heat generated in closed circuit? Can you explain the energy transformation relationship clearly,