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.
My father has an idea is powering vehicle using negative pressure. I'm trying to explain to him that I don't think that can work. He is saying that imagine you're in space and you try create negative pressure by keep on removing and the only thing that's preventing the collapse of the material...
Hello! I have a signal at fixed frequency of 4 MHz and amplitude of 0.075 V. I need to amplify it to ~75 V with the same frequency. I checked online a bit and I found either cheap amplifier that can't amplify this much, or very expensive ones that (almost) can (I might need to use a smaller...
Consider the infrared led TSAL7600 which has the following properties:
$$ \Phi = 35 mW $$
$$ I_e = 25 mW/sr $$
The half angle is ## 30^\circ ## and:
$$ I_r(\theta) = cos^{4.818}(\theta) $$
is a good approximation for the relative radiant intensity.
However, finding the actual radiant...
I need help with part c.
My solution:
Is there an other way to do this other than dimensional analysis?
P.S "dr an infinitesimal radius", it ofcourse should be dz.
Really perplexed me as the answer provided does not solve for mass ... seemingly wants to use mass as a unit of height? Or perhaps I'm off base ... really just curious if this is even correct or possible?
Thanks in advance
The data collected from the experiment is,
The first column is the polarizer angle measured in degrees.
The second column is recorded intensity measured in lux.
The third column is the transmitted intensity measured in lux. This is equal to the recorded lux - ambient lux
The fourth column is...
Hello
I'm trying to use FMESH command to get power distribution of this core geometry.
I want to use xyz coordinate in a 1/12 slice of a core so I could use the output of the MCNP sim for a CFD input
How should I approach this?
Thank you
The statement of the problem is:
Consider a taut string that has a mass per unit length ##\mu_1## carrying transverse wave pulses of the form ##y = f(x - v_1 t)## that are incident upon a point P where the string connects to a second string with mass per unit length ##\mu_2##.
Derive $$1 = r^2...
Hello all, the short story is, I am basically trying to get the same ( or a little more) “power” out of a larger lawn mower type gas engine ( vertical shaft) as one of the largest (120 ish cc) chainsaws ( ref the Stihl MS 880 or newer 881 at approx 10-12k rpm and 9 Hp)
The parameters are : a...
I am currently at a power plant here in Texas and the 480VAC system swings from 480 while equipment is on line and as high as 536VAC when equipment is off line. They tell me that this is prefectly normal but I have never seen swings like this at any power plant. So, is this normal???
Hi there,
I hope that somebody can help me with this.. Any response is much appreciated!
Let's have a vertical closed-loop system where the fluid circulates using the pump. The temperature in both sections gradually changes (the upcomer section is heated up) so that the densities, velocities...
For this proof,
I am unsure how they got from line 3 to line 4.
If I simplify and collect like terms for line 3 I get ##f'(a) = 4a^{n-1}##
Would some please be able to help?
Many thanks!
For part (b),
The solution is,
However, if the acceleration was not constant during the 21 ms, then would the power required be larger?
I believe the average power required would be larger because if the train started off at a lower speed and then speed up very rapidly towards the end...
How can I calculate the stopping power for aluminum in Fluka? I want to send 100 kevlik proton, I add deltaray card to target aliminuma.input file and this card is processing 10 MeV for some reason.
TITLE
* Set the defaults for precision simulations
DEFAULTS...
The classical "power method" for solving one special eigenvalue of an operator works, in a finite-dimensional vector space, as follows: suppose an operator ##\hat{A}## can be written as an ##n\times n## matrix, and its unknown eigenvectors are (in Dirac bra-ket notation) ##\left|\psi_1...
Okay so I am a little confused as to where I made a mistake. I couldn't figure out how to program Latex into this website but I attached a file with the work I did and an explanation of my thought process along the way.
All resources I’ve found for grating resolving power assume uniform distribution on the grating and produce airy disks. Resolvance is determined by the Rayleigh criterion where the peak of one wavelength is at the minima of the adjacent one. This definition doesn’t seem applicable for Gaussian...
How do I calculate the stopping power or projected range for aluminum in Fulka. And in which output file is this data located?How can I edit a change in the input file?
I had difficulty showing this no matter what I tried in (a) I am not getting it. Here for p(t) in K[[t]] : ## |p|=e^{-v(p)} ## where v(p) is the minimal index with a non-zero coiefficient.
I said that p_i is a cauchy sequence so, for every epsilon>0 there exists a natural N such that for all...
So, if I get it right, the basic argument goes like this: AC was preferred to DC because its voltage can be stepped up by a transformer. This limits losses while the current is transported from the production plant to the final user. The voltage is subsequently stepped down when delivered to the...
Power P = F x v,where F is force and v is velocity,
if power remains constant then i think force can not remain constant as it will change the velocity v,
but the solution I found is,
F = ma, v = at,
so, P = F x v = ma x at = ma2 t,
after that calculus comes to show that displacement is...
I have a Multicomp 0-30V 0-5 amp power supply. I did some tests using it as a battery charger. It worked very well the first few times, then I accidently hooked it up backwards and killed it. There was light sparking when this happened. No fuses blew. It powers up normally, and I can...
My thoughts were I could use mesh current analysis to derive equations for current hence power in each case in terms of ωC and R, set the equations for real power equal to each other and solve for R. While ωC are known I opted to leave them as letters thinking this might make life easier when...
This is a piston I had DMLS printed from AlSi10mg - the geometry is derived from generative design using some basic inputs and a starting shape. It's really just an experiment whether a consumer grade design and print can be bolted in and work for a time.
After machining, it is predicted to...
Here is the link to the equation I consider to be correct https://scienceworld.wolfram.com/physics/DragPower.html
Is anyone disagreeing with that and if so can you provide a link or screenshot from a proper textbook ?
The v in that equation is defined as speed of the fluid relative to the body.
Lecture 20 by Prof. Mattuck is simply great. I don’t think there can be any better communication than that, it seemed as if what was in his mind simply got teleported in to mine, and that’s why, it seems now, Aristotle gave so much importance (and almost considered it as a divine power) to the...
Hello,
I'm wondering about the practicality and feasibility of building large power tower structures in space.
I could imagine something like follows:
Take a long structural beam which is positioned in alignment to the sun rays. At the end closest to the sun a receiver is placed. Consisting...
The solution said that Average power= net change in energy/time, but why is that true? If you have a different way of solving it, it would be helpful too
Figure:
My attempt at a solution:
1st kirchoff law:
$$J=2I_0+I_0=6\, \textrm{A}$$
$$V_1+8=10\rightarrow \boxed{V_1=2}$$
$$V_1=6-V_S\rightarrow \boxed{V_S=-4\, \textrm{V}}$$
We are looking for ##P## generated in ##J##
$$V_J=V_1-2\cdot J=2-2\cdot 6=-10\, \textrm{V}$$...
I will like the equation describing the amount of wind power available to a wind powered vehicle driving directly downwind.
I'm interested in the ideal case so max theoretical power available to a wind only powered vehicle driving directly downwind.
I do know what the equation is but I like to...
There is a power line of undetermined voltage hanging just 4 feet above my RV and the stream running next to us. If during the rain, a branch from the redwood tree above us falls and causes the hot line to land on the RV and stay there, is there a way to prevent us being shocked while we try to...
Would it be a feasible power source to have several Stirling Engines sticking through an outdoor wall near your fire place in a cold climate?
Issues I can think of:
Presumably it would be a heat sink and require you to consume more firewood.
Engineering it to not have passive leaks might be...
Large power generators (for example 200 MW) are cooled by H2 in gas form. H2 temperature is +45 to +75 "C. So why hydrogen dew point is important in generator while the lowest hydrogen temperature is 45 "C? And in some Power Stations is monitored online...
Thanks, a lot
Hello! I am sorry if this questions is silly but I really don't know much about electronics.
I have a pulse generator (this one) and I want to test it with a low voltage for now. I have a bench power supply (something like this). I am confused about how to make the connections. For the pulse...
Let ## n ## be a positive integer and ## p ## be a prime.
Then the exponent of the highest power of ## p ## that divides ## n! ## is ## \sum_{k=1}^{\infty}[\frac{n}{p^{k}}] ##.
Observe that ## n=823 ## and ## p=3 ##.
Thus
\begin{align*}...
Hello. I have a question regarding an power amplifier (signal generator). I have three exciters and want to connect them to the power amplifier. One exciter have a impedance of 8ohm and power of 25 watt. The ampliefier have one output with the electical data: 4 ohm : 500watt; 6ohm: 330 watt and...
Hello - thank you for reading this, and thank you in advance to anyone who replies and clarifies the mystery of "ground."
I have finally gained a full understanding of how a full-wave rectifier, two-power tube electric guitar amplifier works in a push-pull manner, but one thing remains after I...
Impossible?!?
By my estimation the equation that describes this motion is given by:
$$Pt = \frac{1}{2}m{ \dot x}^2$$
or
$$\dot{x} = \sqrt{\frac{2P}{m}} \sqrt{t}$$
but this implies:
$$\ddot{x} = \sqrt{\frac{2P}{m}} \frac{1}{\sqrt{t}}$$
So, no matter how small we make the power, we appear...
Why do some UPSs have both Volt-amp and watt rating? According to APC, the connected load shouldn't exceed the UPS's VA and watt rating. Why? If I had a UPS with 1000VA and 500W rating, why can't it power a load consuming 1000VA @ 900W? If a UPS can output 1000VA, why does it care how much...
Summary: Calculating engine power required for semi trucks under different circumstances.
Hello everyone,
I would like to ask you for help if that is allowed.
For a current project I need to calculate engine power needed in watts under different circumstances.
This is something that I will...
Proof:
Suppose for the sake of contradiction that ## 2^{n}+1 ## is prime but ## n ## is not a power of ## 2 ##.
Then ## n=ks ## for some ## k\in\mathbb{Z} ## where ## 1\leq k<n ## and ## s ## is an odd prime factor.
This means ## (a-b)\mid (a^{q}-b^{q}) ##.
Let ## a=2^{k}, b=-1 ## and ## q=s...
If I have a motor with a full load power factor of 0.8 and starting power factor of 0.3 and I install a VSD to run it with a datasheet power factor of 0.95, will the power factor during starting be 0.3 or 0.95? And at full load?
Cheers!
First Assume the following basic circuit:
I read in many textbooks that the electrons in the circuit are accelerated by the positive voltage and decelerated by the collisions, so the speed is constant.
We also know that the circuit current is I = 10A so the power consumed is P = V * I = 100W...
Kathy Joseph makes wonderful videos (and now a book) about the history of electricity. Her research is very thorough.
I just watched the video below, and found it instructive. Especially interesting is how Nikola Tesla and Westinghouse in the USA got the fame and credit for three phase power...
I believe I am doing everything right up until the point where I have to try and find a recurrence relation. I honestly have no idea what to do from there. I've listed my work in getting the powers of n and the indicies to all match. Any help appreciated.
Here is the original DE...