What is Power: Definition and 999 Discussions

A power outage (also called a power cut, a power out, a power blackout, a power failure, a power loss, or a blackout) is the loss of the electrical power network supply to an end user.There are many causes of power failures in an electricity network. Examples of these causes include faults at power stations, damage to electric transmission lines, substations or other parts of the distribution system, a short circuit, cascading failure, fuse or circuit breaker operation.
Power failures are particularly critical at sites where the environment and public safety are at risk. Institutions such as hospitals, sewage treatment plants, and mines will usually have backup power sources such as standby generators, which will automatically start up when electrical power is lost. Other critical systems, such as telecommunication, are also required to have emergency power. The battery room of a telephone exchange usually has arrays of lead–acid batteries for backup and also a socket for connecting a generator during extended periods of outage.

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  1. E

    Checking my answer.... finding the power of a current and a voltage source

    Homework Statement The current source and voltage source in the circuit shown in the Figure below are connected in parallel so that they both have the same voltage, vs. The current source and voltage source are also connected in series so that they both have the same current, is. Suppose that...
  2. R

    I How does the solar wind affect power grids?

    I'm reading about solar wind and the effects it has on Earth. The charged particles from the solar wind have the potential to affect power grids which can cause outages. I know that it is related to electromagnetism, but how exactly does this happen?
  3. T

    Measuring the Power Output of a Generator

    Hey folks, I built a generator for fun and I would like to find out how much power it is producing when I use it. I have a way of measuring mechanical power in but I am not quite sure on how to measure electrical power out. I'm thinking I could use some LEDs to create a load (or maybe...
  4. Delta Force

    Chernobyl Soviet Power Grid Post-Chernobyl

    Did the Chernobyl Disaster have any major effects on the Soviet power grid as a direct result of the accident or due the retrofit and cancellation of RBMK reactors?
  5. russ_watters

    Why is my power washer's GFCI plug tripping and getting hot?

    I have a small power washer with a two-wire cord and GFCI plug. My outdoor and garage receptacles are on a "house GFCI" circuit, wired in series to one GFCI receptalce. Yesterday I tried to use the power washer and the plug GFCI would instantly trip when plugged-in and instantly re-trip when...
  6. N

    High power low frequency RF Amplifiers

    Hi all I am searching some commercially available industrial grade power amplifiers: 1.In the frequency range of 80 KHz to 140 KHz with output power of 2 KW to 50 ohm load in pulsed mode (<10% Duty Cycle 2.In the frequency range of 400 KHz to 450 KHz with output power of 5 KW to 25 ohm load...
  7. C

    How much would a quantum computing network rely on power?

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  8. E

    Calculating Solar Panel Area Needed for a 1MW Power Output

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  9. Spinnor

    Google made headphones, power to translate 40 languages

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  10. P

    Answer for the Given on Steam Power Plant

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  11. W

    Designing a linear DC power supply

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  12. S

    100% energy efficient, constant power rocket

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  13. Cocoleia

    How to Calculate Total Power Factor in a Parallel AC Circuit?

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  14. W

    Battery Power draining even when PC is Off?

    Hi, I am just clueless about this. I turned my computer off with the battery at 100% ( I was using power cord with outlet). I disconnected from the server at the coffee shop, went to " Shut Down" on Windows icon menu, turned machne off. This morning I turn my PC on and the battery is at around...
  15. P

    LCR series circuits and average power

    Homework Statement One type of tuning circuit used in radio receivers is a series LCR circuit. You like listening to a station1 that transmits 99.3 MHz in . The government wants to make 100.1 MHz available to station2. Assume that the transmitters of the two stations are equally powerful and...
  16. G

    Would high voltage DC power grids work the same?

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  17. Asmaa Mohammad

    Medical The power of the human eye's lens

    Hello, I read in my physiology book that when the ciliary muscle relaxes, the power of the eye lens decreases, hence we get the ability to see far objects. I am new to physiology, and when I googled "the power of the eye lens" I didn't find articles explain the sentence above simply. So I...
  18. A

    Why does having a high input impedance and low output impeda

    Homework Statement Say you connect Circuit A with low output impedance to circuit B with high input impedance. Why does this cause minimal voltage drop compared to connecting them the other way around (high output to low input). Homework Equations P = V^2/R P = IV The Attempt at a Solution I...
  19. M

    MHB Understand Proof for Exterior Product Proposition

    Hey! :o I am looking at the proof of the following proposition: Let $\displaystyle{\phi, \ldots , \phi_k\in V^{\star}}$ and $\displaystyle{\psi_i=\sum_{j=1}^ka_{ij}\phi_j, \ i=1, \ldots , k}$ with a matrix $\displaystyle{(a_{ij})\in M(k\times k, \mathbb{R})}$. Then it holds that...
  20. D

    Help intagrating hertzmeter into analog linear power supply

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  21. D

    Total power of a pulsed source over time?

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  22. I

    Electric power and internal resistance

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  23. U

    Blades/propellers - power optimization - drone hovering

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  24. Marcin H

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  25. T

    Analysis of the entropy S of an arbritary system can be written as a power series?

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  26. A

    Selection of multi-pin connector for power lead cables

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  27. D

    Engineering Calculate the maximum power of the resistor in a circuit

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  28. T

    In batteries, does stored energy vary with battery voltage?

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  29. deuel18

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  30. enginej

    Calculating the total power received by an antenna

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  31. G

    Identifying overhead power lines (esp. UK)

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  32. Z

    Estimating Torque from Power over Time

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  33. G

    What Could Be Causing the Malfunction in My Linear DC Power Supply?

    Lavolta BPS 305 0-30V and 0-5A. I was showing a young lad how you can energise a car ignition coil and get a spark on the output, and that this effect can be improved by adding a cap in parallel which forms a crude LC oscillator etc when the unit died. Silly, I know, but we got a bit carried...
  34. anorlunda

    The Perry Report on USA Electric Power

    Find the full text here Staff Report to the Secretary on Electricity Markets and Reliability I really like this report, it's right up my alley. It is professionally done. Every assertion of fact is documented with citations to reputable data sources. I found nothing outrageous in the 187...
  35. L

    B Representation of complex of square root of negative i with unitary power.

    Can ##sqrt(-i)## be expressed as a complex number z = x + iy with unitary power?
  36. L

    I Simplified imaginary unit to the power of imaginary unit

    Where is my simplification wrong?
  37. A

    Can a Car Alternator Function as a Battery to Power a Motor?

    Hello, Is it possible for a car alternator to work like a battery and power a motor?
  38. E

    Understanding RF Power Measurement: Average vs. Composite Power

    What is the difference between average and composite power?
  39. adamaero

    Red (power: pin 2) wire for servo motor not connected

    Why is the red (power: pin 2) wire for the servo motor not connected to anything in this circuit? https://github.com/samyk/combobreaker/blob/master/Eagle Files/ComboBreaker_top.pngAlso, on the "bottom" schematic, the ground is connected to the feedback (potentiometer wiper) line...
  40. G

    How can I represent these resistances on a diagram?

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  41. D

    Input Power against time graph - Flywheel from rest to 300rpm

    Homework Statement gearbox and flywheel are as shown in FIGURE 4. The output shaft rotates in the opposite direction to the input shaft at 5 times its speed. The gearbox has an efficiency of 92%. If the flywheel is solid, has a mass of 50 kg, a diameter of 1.5 m and is to accelerate from rest...
  42. J

    Calculate the power generated by a rotating rod turning a generator

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  43. Wrichik Basu

    Neutral wire in electric power distribution between substations

    I had learned from a book in a lower class that electric power distribution from the generating station is done in phases. Like in India, we have three phases of power transmission: the red, green and yellow colours distinguish the three phases. I believe the same is the case in any other...
  44. Const@ntine

    Ar (Gas) goes into spinner (Adiabatic Decompression): Power?

    Homework Statement Argo, in its gas form, is insterted into a spinner, with a rhythm of 80.0 kg/min = 1.33 kg/s, temperature 800 C (= 1073.15 K), and pressure 1.50 MPa. It's decompressed adiabatically, and "escapes" the spinner with pressure 300 kPa. a) Temperature when it "escapes" ? b)...
  45. S

    Danger and risks of fusion power

    As someone who has had an interest in the potential outcome of various scientific en-devours, I have weighed potential outcomes of things that interest people to be good to potential outcomes they may not have yet seen as being bad. I wonder if anyone has asked the questions about how our...
  46. K

    Understanding Universal Motors in Power Tools: 2 Pole vs. 4 Pole Explanation

    Hi i recently completed my mechanical engineering and was interested in studying how power tools work! when i did some survey i came to know that they work on the basis of universal motor usually. So now the question rises whether it is a 2 pole or a 4 pole? what will happen if its is 2 pole and...
  47. V

    Engineering Job security for Power Engineers

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  48. D

    How many turns to produce power on a spinning coil

    Does anyone have formulae to calculate the number of turns required on a coil to produce 10V at approx 5W. I wish to have a coil spinning on a 16" diameter former in a 0.25 gauss magnetic field at a minimum of 2.2Hz. I need to be able to work out the size of coil and number of turns to produce...
  49. B

    What is the Capacity Factor of Glycolysis in Cells?

    Hello. I'm in the process of teaching myself cell bio and I'm curious to find a good source with actual rates of glycolysis in cells. In a nutshell, I'm wondering what the maximum rate of ATP production within the cell is (assuming a normal yet constant extracellular concentration of glucose)...
  50. T

    Effects of weight in punch resistance and power in boxing?

    I wasn't exactly sure which forum I should post this question in but I felt this was the most appropriate one. So if there is a more appropriate one, feel free to relocate it (whoever is responsible for that). I wanted strictly a scientific answer to this question. How does weight affect a...
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