Measurement Definition and 1000 Threads

Does anybody else besides Fra believe that quantum mechanics' Measurement Problem, Quantum Gravity, and Unification Program of all Forces are somehow related? Why and why not (pls. state or elaborate why you think or don't think so)?

Hello I want to measure the lateral acceleration at the center of gravity of a vehicle. I cannot place the accelerometer here since I cannot mount it properly so I have placed it 75 cm to the left of the CG. The longitudinal and and vertical placement is approximately correct. It there som...

Hi We are measuring 3 Phase Power of an asynchronous Motor-Generator and have equipment installed on Phase 1 (L1) and Phase 3 (L3) to measure the current/voltage/power. I have some questions regarding the results. Q) Why is the Power of Phase 1 positive and Phase 3 Negative ? Q) How can...

Hi, there. I am not major in physics so maybe I lack some basic knowledge. Imagine one have an ideal sensor, which can convert the emission to some kinds of signal (typically, voltage), then what process can describe the measure data? Is it related to...

Hi everybody! Would someone please advise on the following matter. I'm making up a table of railcar operating loads. One of the column includes abbreviated units of measurement such as kN, MN, N/mm2, etc. The question is: How should I title the column? I was thinking about titling it...

In Quantum Mechanics, there are measurement problems and you have many interpretations like Copenhagen, Many Worlds, de Broglie/Bohm mechanics, etc. Are there also measurement problems in Einstein Special Relativity for instance? Can't we consider the following: Spacetime in Relativity is...

The roentgen (R, also röntgen) is a unit of measurement for exposure to ionizing radiation (such as X-ray and gamma rays), and is named after the German physicist Wilhelm Röntgen. Adopted in 1928[1], 1 R is the amount of radiation required to liberate positive and negative charges of one...

how is time measured? if time is 1 sec distance traveled by light is 3 lakh km for that time is "c" now if we overcome this speed we have to go into future,but the problem here is we take light as a reference,had we not taken light as a reference in measurement of time,there would have been no...

Transmission line charateristics measurement?? Dear all, I want to do cable analysis of a 3800m long twisted pair wire to set up a communication system. It is not usual twisted pair wire (telephone), has different impedance, R=194, L=4mH, C=180uF. The things to be analyzed are...

I am thinking of using the output frequency of a 555 relaxation oscillator for measurement purposes. The frequency would be related to my measurement signal. How stable are these oscillators at low frequencies? Any personal experiences would help. How stable can you get then with good...

It is mentioned in the book "Quantum: Einstein, Bohr and the Great Debate about the Nature of Reality" the following: "Once the momentum of particle A is measured, it is possible to predict accurately the result of a similar measurement of the momentum of particle B as outlined by EPR...

Homework Statement according to the measurement postulate of quantum mechanics what happens if Q-hat is measured, followed immediately by a measurement of a compatible quantity R-hat and then a further measurement of Q-hat? you may assume that the eigenvalues of Q-hat and the eigenvalue of...

Hello Everyone, My statistics is terribly rusty so I am turning to all of you for assistance! I am in the process of reviewing my old text but I figured this may be quite a bit quicker. Homework Statement Suppose "x" is normally distributed with "mu_1" and "sigma_1." Now suppose x is measured...

There are lots of for metal cutting measurement. However, thermocouple is not in the list of metal cutting measurement. Anyway, is it possible to measure the temperature for turning machine by using K-type thermocouple. Can i put the thermocouple at the end of cutting edge to measure ? can it...

Hi everyone, How do u measure temperature, let's say of a car bulb without using a thermometer? Your ideas are all welcomed. Thanx

I am going to use tool work thermocouple to measure the temperature but i am facing a problem. I know i can use steel strip to one of the wire. but how about the second wire? If my insert is Titanium Carbide. Is it ok if i using different material from the insert to connect to second wire ...

How do flux meters work ?? On what basis they measure the strength of field please share the link (Urgently required)

Question Suppose molecules are placed next to the slits that fluoresce when electron passes, emitting a photon that can be imaged. Explain why this is no better than direct illumination, and explain how the two-slit interference pattern is destroyed. My Answer In direct illumination, a...

(This a new thread as proposed by Borek post #2349) Neutrons and neutron "beams" are very hard to detect with portable instruments. The most common portable instruments are gas proportional counters using thermal neutron capture in BF3 (boron tri-fluoride) or He3 gas. Proportional counters...

Say we have two particles with angular momentum basis states |j_1~m_1\rangle and |j_2~m_2\rangle and the combined system is in the state: |0~0\rangle=\sqrt{\frac{1}{6}}\left(|1~1\rangle |1~-1\rangle+|1~-1\rangle |1~1\rangle\right) What is the probability that measurements of the...

I've been looking at the level measurement data from the Fukushima plants during the accident, and wondering if the somewhat suspicious behaviour is due to clogging of the impulse tubes ore some other malfunction, or if the measurement is arranged in such a way that it does not measure the core...

Never do we change a completely imagined, clearly defined linear measure. We don't change the fahrenheit scale as we use temperature measurements. Humidity, radioactivity, velocity, weight- None of these are ever manipulated. I hope this helps to make a point. Why does it automatically make...

Hi there when doing an experiment with my university associated with my university related to a simple pendulum, I was not confident when calculating the error there was in my measurement, the relevant equation is: T=2\pi\sqrt{\frac{L}{g}} where T=period L=length of pendulum and g=accel...

Hi, I would like to measure the signal noise in a tv cable after introducing a splitter and compare it with the original signal. Keeping in mind the bandwidth frequency of the tv cable signal transmission, what kind of instrument do I need? Oscilloscope perhaps? At what speed? I don't know...

Two doubts... 1. Consider two frames S and M, the latter moving at constant velocity v wrt S. I know that it's possible to synchronize clocks at different positions in a particular frame. But is it possible to synchronize a clock in S and another in M, and if so, how to do it? 2. Suppose...

Temperature measurement can be categorize into...how many ? Temperature measurement by mechanical effect.. Temperature measurement by electrical effect.. Temperature measurement by radiation.. am i right ?

Here's a quote from Einstein's 1905 paper regarding evaluation of times of events occurring at places remote from the observer : Please explain the meaning of that last sentence. I mean, where and why does the disadvantage of using the above method arise?

first of all, I'm a new bie of QM, with q1,p1 and q2,p2 the couples of position and momentum THE QUESTION IS: can I just measure a \hat{q1} with no measure of \hat{q2}? and how? and how I calculate the new wave function with the dependece of q2? I hope that \hat{q1}|q1,q2>=q1|q1,q2> is...

I need to design a scale. It is a simple 2-D problem. All you need to know is that it's a plate on a vertical spring. Each end of the plate slides a little ways into an indent. It is a scale for weighing ingredients in a bakery. A weight of 22lbs (+or- .25 lbs) is acceptable. If there isn't...

Hey, I am working in a lab and I simply can't figure out a method to measure the pressure between two plates I'm compressing. Here's my set up: I have a metal plate with perpendicular screws attached to another metal plate (I will be putting my sample between these plates). All I do is...

What is the best way to measure the voltage from a high resistance circuit? The circuit resistance is higher than the resistance of the voltmeter.

Can anyone help me with our investigative project in physics? This is just a very simple project. Our experiment is all about the effect of salt on the rate at which a glass thermometer measure a sudden change in the temperature of a solution. The thermometer will first be allowed to be at...

Hello everyone, The students of our college wants to start a club for measurement. We were thinking that our college should give more opportunities for our students to be creative with the methods of physics and so, the idea of this club arose. We will take contact with one of our donators, but...

how to measure porosity, porosity factor and void factor of a solid mixture?

How to measure density as much precise as possible. Possibly with a waterproof balance under watter. What the prices are?

Homework Statement hello, I have ten results of measurements, all are identical, and how i can count error? it is this: L = ( 20 \pm 0,1 ) cm and all errors, mean squared error etc are 0, how can I count this now?

If we measure a quantity with 2 different tools(once by direct measurements and the other time through simulation), is it true if we compare these 2 results together by using paired t test? Does it makes sense ? For example we want to measure the aborbed dose of a patient, so once we measure...

In school we somehow measured the minimum and maximum wavelength our eyes could see Unfortunately, all I remember is that we were looking through a slit between jaws of some sort of calipers and used a ruler to do measurements Can anyone please give me an insight of how to set up such...

<Pic> This is the theory of ammeter give in a book. please read it. Now, my question is that coil will only respond to the current through it i.e. i1. But this is a very small part of total current (Rc >> r). Does this mean that all the moving coil ammeters show wrong current? Please...

Mass, Charge, Spin has definite properties before measurement. What else aside from position, momentum that have NO definite properties before measurement. Is it only position and momentum?

Add One "Dollop" Hello; I have tried to be as accurate as possible with my measurements while cooking and I have done fine so far, but what exactly is one 'dollop'? I have been told to add one 'dollop' of mayonnaise and I have no idea what this means. I am assuming it is not a small...

Homework Statement This is an extension to problem 4.55 in Griffiths. The problem is: The electron in a hydrogen atom occupies the combined spin and position state: \lvert \psi \rangle = R_{21} \left(\sqrt{1/3} Y_1^0 \chi_+ + \sqrt{2/3} Y_1^1 \chi_-\right) a) If S_z is measured, what...

When electrons are passed through a double slit and can either display a wave-like interference pattern or a particle-like build-up pattern, is that because their momentum/direction is changed by the measuring device interacting with them, or due to some other feature associated with being...

I just watched a show on Einstein concerning this theory of general relativity. Around 1922 photographs of stars from an eclipse were used to measure the bending of light from those stars around the gravitational field of the sun. Those measurements were used to confirm Einstein's theory. All...

As we all know, the current should be measured in series with the multimeter... However, how do we connect the multimeter in series with home appliance without damaging the wire(plug)??

I am interested in how PSD (particle size distribution) affects the transmittance of a material and I am trying to find an accurate process to measure it so that I can test and gather data on how it affects it. I don't know if transmittance is the proper word for what i want to study, but all...

How do you do a Bell measurement on a state that doesn't have a power of 2 number of qubits? I've got GHZ states like this: |GHZ_{ijk}> = \frac{|0_{i}0_{j}0_{k}> + |1_{i}1_{j}1_{k}>}{\sqrt{2}} And I'm trying to Bell measure the following state at qubits 2 and 3...

Question: Among six measurement of the boiling point of a silicon compound, the size of the error was 0.07,0.03,0.14,0.08 and 0.03 degree Celsius. Assuming that these data can be looked upon as a random sample from the population given by f(x;\theta) = 2(\theta-x)/\theta for 0<x<\theta =0...

Doppler shift of light shows distant galaxies moving away from us at high speed. This of course has been taken to prove that the universe itself is expanding and it has been theorized that the expansion is accelerating. To actually empirically measure and prove the theorized acceleration...

Homework Statement An initial state is given: {\lvert {\psi(0)} \rangle} = \frac{1}{{\sqrt{3}}} \left( {\lvert {100} \rangle} + {\lvert {210} \rangle} + {\lvert {211} \rangle}\right) An L_z measurement is performed with outcome 0 at time t_0. What is the appropriate form for the ket...