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. nagyn

    Induction stovetop design: am I using these equations correctly?

    I've been told an effective induction stovetop needs to deliver about 1000W of power. I have magnet wire that can tolerate at most about 0.2A of current, and was planning on using a 60Hz wall outlet as my source (obviously I'll need to bring down the outlet current quite a bit). So the energy...
  2. G

    Suggestions for research topics for M.Sc. in Nuclear Power Engineering

    Summary: Suggestion on experimental research related to reactor for master's degree dissertation. Summary: Suggestion on experimental research related to reactor for master's degree dissertation. I have just started my master's degree course in Nuclear Power Engineering and decided to...
  3. K

    Buck converter will power LED's but voltage divider will not....

    Summary: Am seeking help understanding why when I take my battery (50V max 44 nominal; 15aH capacity; 12s5p) and attempt to step down the voltage that sometimes it works and sometimes not... Hi all, New to forum. Chemical engineer seeks help from electrical engineers... Thanks for reading...
  4. S

    Power equations, which equation to use and why?

    Which equation do I use and why do I use it? I think it would be P = V^2/R, but why do we exclude current the from the equation?
  5. R

    MHB Solution to function with power greater than 4

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  6. Indula

    A Does molybdenum react with an Argon plasma powered by RF power?

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  7. Physics lover

    Maximum power in this resistor circuit

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  8. Izazo

    Calculating Steam Turbine output power

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  9. M

    I need to know the power of a flywheel

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  10. E

    Having difficulty increasing my load power factor above 0.95

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  11. T

    Flow rate of steam in power plants

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  12. D

    Why does a Polywell Fusion Reactor not generate net power?

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  13. J

    Electric mining truck creates electric power

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  14. P

    Potential of the terminals on a DC power supply

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  15. M

    Inverse Power Law: Solve for Power at 400m

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  16. A

    I Calculate Retinal irradiance - from photometric units

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  17. Prialen

    How to choose the right power screw dimensions given the maximum load

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  18. kolleamm

    High current power supply for servos? 40+ amps

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  19. gleem

    Three mile Island Power Plant to be Shut Down

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  20. M

    How to characterize a power law field?

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  21. F

    Hydro Power is Actually Solar Power

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  22. L

    Thermodynamic Systems - Power rating and thermal efficiency

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  23. K

    Question about power extension board

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  24. K

    Any problem when a home power switch is staying between ON and OFF?

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  25. karush

    MHB 215 AP Calculus Exam Problem Power Rule

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  26. S

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  27. NTL2009

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  28. T

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  29. L

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  30. dvscrobe

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  31. J

    Power Loss in Transmission Lines: AC vs DC Comparison Explained with a Model

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  32. Don Bori

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    Hello there! So confused here, I tried to do some calculations with my power generation experimention. In terms of energy input, the energy output is lower. But in terms of power input, the power output is way larger. Thanks in advance! Cheers!
  33. Michael Price

    A Resolving power of a radio telescope array: Quantum or classical?

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  34. person123

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  35. A

    Active power dissipated by a resistor from DC to RF

    Hello all PF members! I was wondering about the power dissipated by resistor at high frequency which is: ##P=Re\left \{ U\cdot I^{*} \right \}=Re\left \{ \frac{\left |V^{+} \right |^{^{2}}}{2\left |Z_{c} \right |}\cdot (1-\left |\Gamma \right |^{2} )\right \}##, (1) where: ##Z_{c}## -...
  36. E

    How much computing power would you have if....

    This is a hypothetical question, but.. How much computing power would all the computers in the world combined have? Would you have a at least one YottaFLOP?
  37. M

    Overvoltage on the power supply to compressor motors

    Hope you may help me to understand how detrimental to compressor motor would be if it operated at voltages exceeding the manufacturer's specified 400V by 12%? so 448V. I have vendor engineers saying since it exceeds 10% they cannot safely run the plant and of course the voltage monitoring relay...
  38. D

    Electrical Enclosed water turbine power generation

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  39. J

    Fusion power generation: percentage of neutrons expected to be caught?

    Surely the real efficiency of Fusion power is the percentage of neutrons that can be caught to extract kinetic energy from. I am assuming it is the neutron that is carrying the nuclear energy that can be recovered from the fusion reaction. Now I'm pretty sure neutrons cannot be focused, so the...
  40. MatheusMazur

    Power spent to keep a spring compressed

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  41. og_ogun_srvs

    Current or Power Reference Tracking with Power Electronics Converters

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  42. A

    1-10 kV power supply recommendations DIY electrostatic motors

    I am trying some projects that involve building some very simple electrostatic motors. I attached below figures of the kind of electrostatic motors I am trying to make. What I can't figure out is what kind of high-voltage power supply I should use, presumably 1000 to 10,000 volts is what these...
  43. G

    Power supply for testing: Variac or isolation transformer first?

    This is for safely powering up devices being tested/repaired. Supply is 240V rms single phase, protected by 32A MCB and 30 mA RCD/GFCI, then fused at 13A. There doesn’t seem to be a consensus online, and my EE and repair books just say I need both, without specifying order. I think the...
  44. F

    Find the real power consumed using MATLAB Simulink

    My work is attached below. I want to confirm my answer. Any help would be greatly appreciated !
  45. H

    Timer based switch for a power capacitor

    To cover transformer loss at no load and maintain pf, we are needing 6kvar at day time and 9 kvar at evening. Is there any time based switch available, such that it can switch ON 3 kvar at evening, say 8:00pm and turn off automatically at 8:00AM morning
  46. M

    How is it possible to use only 1000 W to transfer 10,000 BTU/h?

    Hi, I was reading a newspaper article on the energy efficiency of commonly used air conditioners in homes. Then a doubt arose when the article informed me that there are air conditioners that have an energy efficiency of 10 BTU/watt. That means a classic 10,000 BTU/h air conditioning machine...
  47. G

    Automotive How much power is needed to haul a weight up an incline at a certain speed

    Good afternoon everyone, I need help with a certain calculation. How much power is needed to pull a 250lb load up a 45 degree incline at 5 mph. I am working on a project at school and would like to know what kind of motor we can use. Thank you very much!
  48. N

    Could Radioisotope Thermoelectric generators power electric cars?

    Could electric cars be given longer range by radioisotope thermoelectric generators like they use to power spacecraft in deep space?
  49. F

    Query about the time average of an AC power supply

    Hi there, I have a query about electric power in AC systems. I am Chilean, and over here the power supply is 220 V (rms) at 50 Hz. Some countries use voltages in the range 200-230, but others use 110 V or so, at frequencies of 60 Hz. There is no uniqueness, but all work. My question is...
  50. Pushoam

    Power being transported down the cable

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