Quality Definition and 205 Threads

hello all, I am having a hard time deriving the proof for the quality factor theorem stated as such: Q = 2 pi {Peak Energy Stored/Energy dissipated per cycle}. the wikipedia article is http://en.wikipedia.org/wiki/Q_factor and I am working to solve the proofe showing that Wnot/deltaW...

From what I understand, bioengineering (as opposed to biomedical engineering) is a very new undergraduate program/major. For example, I think Caltech only started their undergraduate bioengineering "option" (major) this year. How are the qualities of these programs? I only have one data point so...

Homework Statement My book defines the equation for energy of an RLC circuit to be E = 1/2 L I^2 + 1/2 Q^2/C In series the Quality factor is (L/C)^1/2/R My question is will these equations hold for an RLC circuit that is parallel. I.E. the Resistor is in parallel with the Inductor which is...

Hey guys! Just wanted to inquire about the following relationship. Given a boiler and all the water content inside is above boiling point. Would the dryness factor (vapor quality) decrease or increase with pressure reduction. Example we start at 500 kPa then move down down to 400 kPa. Would the...

Is there a difference in the quality of gasoline among different companies? I see Shell gas station sells premium unleaded (9/10) for 3:00/gallon, and across the street, Rotten Robie sells the same premium unleaded (9/10) for 2:60. I assume shell station might provide a better service (accepting...

sorry if i posted this in wrong section.. im having problem on where the value in the circle come from,can someone give me an answer or a hint. TQ

Being a bit of a movie buff, I tend to pick things apart, as I'm sure many people here do. Here is one that came up recently: Is Jeff Goldblum a quality actor, or is he just someone that people like to watch? While I tend to enjoy his movies for light entertainment, I started noticing that he...

Quality of Phd in US or Germany... Hi folks... I want to do phd in computer sc. but could not make up my mind to select the destination country whether US or Germany :confused:. In US the phd duration long compared to Germany, in Germany funding is also good but in us the University s' are...

hi I am new to the this forum I do not know if this topic is to be posted here I am fan of bollywood films (indian).I do not know if the members of forum have watched or not. The bollywood film is emotionally so powerfull to me.I am always fascinated about this. It is second largest film...

Hi, I am trying to understand the solution to a quiz I had, and am having trouble. The question was: The solution says: First off, why (when they solve for internal energy and specific volume) do thy use the formula (Quality)*Uvapor + (1-quality)*Uliquid ? This makes sense to me in my...

Homework Statement Prove that the quality factor of a rectangular cavity resonator which is filled with a lossy dielectric but has perfectly conducting walls, is given by Q = \frac{1}{\tan\delta} where \tan\delta is the loss tangent, i.e. the ratio of the imaginary part of the dielectric...

Water Quality Index equation and math help! Hi there, I am an arts student who, due to signing up for classes very late in the semester, has been stuck with an environmental sciences course. This course was just fine until I got our final assignment, which is a Water Quality Index lab. The...

Any suggestions how I can improve the quality of STM (scanning tunneling microscopy) images? And how can I trace artifacts?

Homework Statement A rigid container of volume 1 m^3 contains saturated water at 1MPa. If the quality is .10, what is the volume occupied by the vapor. Homework Equations The Attempt at a Solution I wanted to use the equation v=(1-x)(v_l)+x(v_v) where all v's are specific...

My XBOX 360 has broken four times now, I have Vista which is a complete disaster, and my Zune doesn't even work with the operating system that they made. I would start buying products from a new company but many other companies are even worse than Microsoft is.

They are playing some really nice christmas songs on the classical station: https://www.youtube.com/watch?v=Z_-uUjsx3ao It's good quality christmas songs too, none of that celine dion crap. I can't find it on youtube, but its Kathleen Battle - A christmas celebration

Hey. I am a first year engineering student, and currently working on a design project. Part of the project requires me to investigate the effect of certain water contaminants on the effectiveness of clothes washing detergents. I am dealing mainly with water sources in Cambodia, so i am looking...

Hello, In Power Quality, how does starting of large motor will cause voltage sag? How does voltage sag cause the motor to stall and overheat? A friend mentioned that it has something to do with sustaining the source power, but I simply don't get it. Thank you in advance.

What are the things to try and control when attempting to burn a high quality audio CD for my CD player in my truck? I am sure there is a bit rating on the file, but are there other things that I can change to get better quality out of my burns? Do better quality CD's make a difference...

Years ago i bought two Ralph Loren (spelling) shirts they are still going strong but are a bit faded, they are made from real tough material and have good length tails. Also 501 button jeans, i can not find them in Uk do they sell them in the USA.

A quick one for you sparkies... There are a ton of FM transmitters you can use to pipe your iPod or other device over your FM stereo. There is one thing in common to the three units I have tried that is very annoying. I have noticed that there is very poor sound quality for the higher...

Best quality oils I know extra virgin olive oils are one of the best. What other oils are of that quality and not needing to be cooked?

Working through my lecture summaries, I have been given that Q (the quality factor) =\frac{2\pi}{(\Delta E/E)cycle} and accepted this as a statement, taking \((\Delta E/E)cycle} to mean the 'energy loss per cycle'. The notes carry on to say 'The frequency \widetilde{\omega} of...

This is one of my favorite boards on PF, but it doesn't have a lot of posts, and I do not know enough about history & historical humanities to ask questions or make many posts. Are there any quality forums that I might like?

"Distances among galaxies in clusters on average are no greater than their diameter". Luminosity, color, and other qualities are used to obtain distances - and these values are connected to masses that are observed by motions. If a system is in equilibrium then the theorem is: 2T+U=0 Mv^2/2...

I was at the mall the other day and I walked past the watch store. I always wanted to know what makes a Rolex so expensive. I know they are made out of real gold and diamonds, but there are some nice rolex watches that are all steel with none of the bling. But those are equally expensive, why? I...

So, I did my research when choosing schools to the best of my ability. I picked a school that was listed in the top 50 schools. I visited the school a few times, talked to some students, researched online, and in publications, and decided. Well, I have been here a few quarters, and I am...

How to become a quality physicist? Hi I am a 21 year old male. Im studying in final year of electronics engineering. However my true love is theoretical physics. I read a lot of graduate level physics textbooks however i can digest very little. as a result of which i have become extremely...

hey was wondering Which are the best Fighters in the world ? An american F type, a Dassault, or other ? Which are the best tanks in the world ? Which are the best attack subs in the world (those to attack sea, and those to attack ground) ? Which are the best Nuclear capability subs in the...

Correct me if I'm wrong. I've always taken it on faith that the switch to frequency modulation from amplitude modulation resulted in the much better quality signal and listening experience we have today. Modulation of the frequency is likely less susceptible to distortion than is modulation...

I read that the higher the temperature of a substance (for example gas) the higher the quality to extract work from it. But for the same substance, at same temperature, it would have high entropy as well which accounts for disorderness and hence less availibility of energy. Please help me...

which brand magnet wire is considered the highest quality, Belden seems to come recommended, any others would be appreciated

Why is that i always see and hear people complaining about textbooks? It is true that there are many bad textbooks but why do they buy them? Can't they read reviews or ask around like i do? Also there are many good textbooks and as a self learner I think my opinion counts for something. A...

I am working on research project on the topic of the quality of education in Canada and the U.S. I was hoping to collect some raw data from university/college students so please answer the poll as honestly as possible. All information will remain anonymous. I will be posting 3 polls, this is...

I need some help deriving the quality factor in an rcl circuit Q=Lw(sub 0)/R. So far I know that Q=w(sub 0)/delta but my professor used this formula to continue the derivation delta w=R/L and I don't know where it comes from. Can anyone give me a hint?

One of the most difficult topics several years ago was weak acid and weak base equilibria and associated mathematical determinations about them in quantitative chemistry. Our class spent a month and a half just studying equilibria of weak acids and weak bases and their buffers, pH's, titration...

My idea is : electricity can be transferred 100% into heat. Mechanical energy can be as well. But heat can not be transferred completely into electricity or mechanical energy. From that point of view, I think that electricity and heat and... are all some forms of energy, but the quality of each...

what does the soundwaves of a poor quality sound look like?? and richer quality?

Another question. If your given the quality coming out of the turbine. Why do you use say H2 = Hl + xv(Hv - Hl) to determine a xv even though u hav one given?

Help please, is there such a thing as a wireless web cam that i can just use with out any mods or additions to my desk top? I need one with good picture and audio quality, and i need it to work 4yrds from the desk top. If there is no such thing can some one recommend a standard one for up to £50?

Hi all, Does anyone of you know the ways in which dose administered to a patient can be minimised while still obtaining a useful X-ray image ?

The reason why this thread is here instead of the Earth science files, will be clear in the last sentence In the spring of this year I received a discussion-group E-mail with an early draft of this paper: http://www.pnas.org/cgi/reprint/0606291103v1.pdf Emphasis mine. As a reaction...

Is good design one of the greatest factors of high-performance technological products?

A friend of mine has given me a link to an amusing movie clip that was supposedly shot on a Nokia N90 but the video quality is so good I believe that its been 'enhanced' afterwards. He swears that the N90's video quality is the best available at the moment but I still think its been doctored...

Someone here has worked out a way that applies to physics: http://math.ucr.edu/home/baez/crackpot.html Anyone wishing to try and apply it to maths? I think it will be an easy transition :smile:

How loud does brown noise have to be for it to be effective?

Hi everyone, Can you please tell me some good reading material on solid/ applied mechanics available on the internet? i want downloadable links or may be good informative internet sites where i can get basics of solid mechanics and applied mechanics. Hope someone helps. Thanx.

Hi all I read that Q,the quality factor of series resonant circuits is wL/R ------------>1/R sqrt(L/C).This i understand 1.but for parallel resonant it is R/wL...hmm but why is that?this i don quite get. 2.Then what do u mean by loaded resonant circuit and unloaded resonant circuit...

I asked a few months ago but didn't get a response so i'll try again :) I'm considdering going to USA for one year as an exchange student, but i must admit that my motivation for it is less then academic. I'm picking it almost solely because i want to train in USA, and my coach there has a...

What is the difference in quality between DVD and VCD? I don't notice that the main difference in image clearence quality.