Quality Definition and 205 Threads

The photons get absorbed according to quantum theory by an electron for Instance in an atom form this phenomenon can anyone explain me reflection ,refraction and scattering of light in photon point of view and not by wavetheory

... in scientific papers? I'm having a real problem with Microsoft Word getting all the information I need onto the graph, it takes up too much room, example: My attempt a TABLE in Word: How I want it to look: So just wondering what you guys use, or how you would go about creating the...

Homework Statement Case, P[bar], T[C], v[m3/kg], u[kJ/kg], x[quality], State a) 1.5, ?, ?, 3000, ?, ? b) ?, 120, .6, ?, ?, ? c) 3, ?, ?, 2543.6, ?, ? d) ?, 190, ?, ?, 20%, ? e) 25, 100, ?, ?, ?, ? f) ?, 240, ?, ?, 0, ? Homework Equations We are supposed to use the steam tables in the back of...

I'd like to learn how I can better understand research papers/scientific studies, judge the quality, the methods used, find out who funded it, etc. I'm a layperson. In researching various topics, especially controversial subjects, I try to find the actual scientific papers behind everything...

I was wondering where I can find the best quality lecture videos of Walter Lewis. Both mechanical and EM. Most of the videos I find are of low quality and it makes it hard to follow. Thanks.

Was wondering if anyone here knew of quality white board markers. I do not like expo brand markers (cheap quality), these are for my personal use. I do not mind paying a bit more for quality. Ie I use tombow mono 100, lumograph, blackwings as my writing pencils. I remember a professor had a...

industrial quality, water proof with corrosion resistant connectors. something a public aquarium would use. it doesn't matter if their capacitance, resistive or voltage sensing. maybe I should have posted this in the chemistry forum but it doesn't really mater I guess.

Homework Statement How and why does quality factor change in a series RLC circuit when the resistance in the circuit increases? I've made a small experiment circuit which looks like one in the picture: The current frequency is 1 kHz and the voltmeter should show 2V throughout the whole...

Hello, I'm not sure if this forum is the right place for this. My son is a Junior in High School, he wants to have a career in Physics. We have been trying to find the right school for him in the northeast, where we live. It has been difficult, however, to determine which schools have great...

I apologize in advance for not being physics savy. My question stems from my interest in loudspeaker behavior, but I think I need to clear up some more basic physics. I'm trying to understand what determines the Quality factor of an oscilator/resonator. Given 2 system's with identical spring...

Hi, I'm trying to simulate dynamic effects of current in terminal box by using Ansoft Maxwell, but the following error occurs: "Mesh quality of some elements is not accepted by solver." Can anybody help me please?

My high school chemistry teacher tossed us the task and told us to figure it out ourselves. As far as I can understand, the trick is to supersaturate the solution, put a seed on a string and hope for the best. I'm just posting here to ask if anyone happens to know any good sites I might not have...

I know that energy has quantity but what it means that energy has quality also?? what it meant by quality of energy?

I stumbled across this. http://www.innovatoys.com/tech-gadgets/usb-eyepiece-for-microscopes/5937 I've got a 6" reflector on an equatorial mount. At some angles, an hour of viewing could put me in a chiropractor's office. It would be cool to observe the sky from a sitting position that didn't...

Hello all. I was wondering if there is a method or a device to check the quality of the twists on twisted pairs cable harness vis-a-vis EMI. i.e. someway (to tell is the twists are good enough to pass EMI testing). Cheers

Hi I am curious to know if quality factor of a resonator depends on the excitation signal or if it stay the same irrespective of the signal applied? Thanks

Homework Statement By what factor does the amplitude decay in the time interval (which I had to find). E: stored energy γ:damping rate a: amplitude t: time Q: quality factor T:Period ω: frequency Homework Equations Q = 2∏E/(ΔE) The Attempt at a Solution I found the interval to be t=QT but...

Is there any way to enhance low quality and low resolution JPEG images? Is there a program I can use or something? I have dozens of grainy and poor quality JPEGs that I would like to sharpen up, but I do not own photoshop.

Can anyone tell me about some cheap and good quality mosquito traps available in delhi India probably online for collecting mosquitoes for a research.Also if there is an easy way to make them ourselves at home but the problem is that i want 25 such traps.so please suggest a feasible way?

Hi All, I have access to a 15kW VFD for little money. I only have single phase 240 vac at home, and need to drive a 10kW motor, 3 phase, 415v. I have been reading that 3 phase input VFDs can be run on single phase, but they must be derated by 50%. This would mean a 20 kW VFD. Also, it is a...

My problem is a general one concerning how to best visualize/get a good mental construct for what's happening when we get simple units by multiplying dimensions other than length^2 or length^3. I don't seem to have any trouble with the intuition about the quotient of values: the notion of 'per'...

What can a PH meter tell you about the quality of fluid it is measuring?

I am currently undertaking a HND in Electrical Engineering and for my graded unit project I have chosen 'Power quality in renewable energy systems'. I was hoping someone could recommend a good book to help. Thanks

Hello. I developed an algorithm to detect events in time domain and I want to know the efficiency of the algorithm. The problem is related with the time duration of the data. Each file has data with a time duration of hundreds of minutes and I have dozens of files. Instead of...

Good morning, I have been researching into a possible astronomy or astrophysics educational plan but my research is not looking too promising. I am enlisted the in the military currently so due to the premise of moving anywhere in the world at any time plus deployments online courses are...

Hello i have to derive the quality factor Q i must start with Q=2\pi\frac{internal-stored-energy}{energy-loss-per-cycle} the quality factor should be in terms of λ so the last equation shall be Q=\frac{4\pi L}{\lambda (1-R)} i searched in google but i always get the Q-factor in...

Homework Statement Show that the fractional change in the resonant frequency (\Delta \omega/ \omega_{0}) of a lightly damped simple harmonic oscillator is ≈ (8Q^{2})^{-1}. Homework Equations Is this a formula for the resonant frequency? \omega_{m} = \omega_{0}\left(1 -...

CPR Quality -- avoid leaning between compressions ? This is the first I've heard of "avoiding leaning between compressions". Does anybody know what that means? All I can find so far is the statement itself, not an expansion/explanation on what leaning means. Maybe they just are trying to say...

Hi, I would like to know, how do I evaluate the quality of correlation? Specifically, I have a set of N datapoints, each represented by k features. I want to know how the k features correlate with each other, and therefore, I created a k by k correlation matrix. I am using R-value, so the...

Homework Statement If you have a mixture of saturated water vapor and saturated liquid water at a pressure of 5000 kPa, and you measure its specific volume to be 0.03181 m^3/kg, what is the quality of the mixture? Homework Equations Nothing is given :( From lectures I found vtot =...

Homework Statement My tutor's notes say that quality factor is supposed to be = 2π (Max. energy stored)/(energy dissipated in one cycle) . So for a standard series LCR circuit, he says: max energy = 0.5 L I2 energy lost per cycle = 0.5 R I2 2π/ω . ..and at resonance he calculates it to be...

Here are my problems I'm experiencing, I'm sure my note taking is very relative to the fact that I have to study 6-8 hours a day to keep up (Or more!) I was wondering if anybody has any tips to improve efficiency and effectiveness of my note taking so that I can spend less time trying to...

Hello everyone! This is my first post on PF, but I've been reading the forums for some time now. My question is rather a simple one, but since I'm an Electronics Engineer, I think it would be polite to say a few words about my education and work experiences. I've finished 4 years of...

Homework Statement Consider a 210MW steam power plant that operates on a simple Rankine cycle. Steam enters the turbine at 10MPa and 500°C and is cooled in the condenser at a pressure of10kPa. The adiabatic efficiency of the turbine and pump is 85% (a) the quality of the steam at the turbine...

Hello people, I am wondering if anyone is familiar with these brands of oscilloscope. I would like to know so I don't end up investing in something that breaks in a 2 months ATTEN ADS1102CAL 100M Hz 1G Digital Oscilloscope 7" LCD -price $336 OWON 100Mhz Oscilloscope SDS7102 1G/s large 8"...

Homework Statement A 4 cubic meter rigid vessel contains 0.04 cubic meters of liquid water and 3.96 cubic meters of water vapor at 101.325 kPa. What is the quality of the saturated vapor? Homework Equations Specific volume of saturated liquid at 100 C and 101.325 kPa: 0.001044 m^3/kg...

hi, first post here if this is too long to parse please skip to the actual question in bold, at the end :) I wasn't able to find any other concise title for this. maybe some of you are aware of the fact that in audio some give great importance to cable selection. for some the audible...

Because obviously too much density gives terrible sound quality, like in water. So is the answer simply the density of our lower atmosphere because that is where our ears evolved? Or has this been tested and found to be a specific density?

Both the copper wire and the light bulb became hotter and hotter when a current was constantly passing through them, resulting in an increase in their resistances, which in turn lowering the value of the current through the conductor. (I did not allow time for both the wire and the light bulb to...

I can't seem to find an answer to this. The question is: If I obtained Deuterium oxide from let's say a plant that manufactured it in some part of the world, and then obtained Deuterium from another plant manufactured from some other place in the world, is it possible for them to have...

Hi.. I have sample data from a normal distribution and I need to estimate mean and variance for the population. For the sake of study I need to use different methods for estimating these parameters and maybe make a comparison of these methods regarding my case. Any idea how to proceed in this...

if possible could you tag some good video lectures may be feymann or any other good source..thanks...!

Hello all, I am new to the forums here. My background is biochemistry and I currently work in a medical laboratory. What brings me here is a new found interest in physics, in particular, quantum theory. I would like to learn much more ranging from the basics to M theory etc.. I would...

Real time water quality data This is data being taken NOW. Note that it links to several sites around the US.

Hi guys I am assigned to do the indoor air quality measurement in 5 buildings which are 2 academic buildings, one residence, a library and a gym. I have to establish a methodology to measure CO2, temperature, humidity, air movement as well as particulates. I have 2 months time to measure and...

Well If we talk about the quality factor of any circuit, we say that: It is the ratio of natural frequency of any circuit and the band width. Q = ω0 / Δω Somewhere I read : It is the ratio of the P.D. across the capacitor or the inductor with the P.D. across the resistor in any...

Homework Statement What does it mean physically if Q < 1 for a particular circuit? What would happen, for instance, if a switch were suddenly closed which completed the circuit by a wire rather than the ac supply? Homework Equations I've already derived the equation for Q (the...

Homework Statement Saturated steam with a pressure of 30 bars is isentropically expanded to a pressure of 1 bar. What is the quality (x) of the steam after expansion? Homework Equations No clue. I do have a table containing all necessary data such as temperature, specific volume...

I am a high school student who has finished calculus, multivariable calculus, and differential equations, but I feel as though the treatment I received of those topics was rather inadequate and shallow - lacking mathematical rigor, so to speak. Can anyone comment on the quality of those two...

My purpose is to learn physics, chemistry and biology.I don't want to have a PhD level knowledge in 3 days, but I do want to have a better understanding of how the world works and be able to do things myself.Not in 3 days of course, but I like short(depending on subject) and clear explanations...