Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. The scope and application of measurement are dependent on the context and discipline. In natural sciences and engineering, measurements do not apply to nominal properties of objects or events, which is consistent with the guidelines of the International vocabulary of metrology published by the International Bureau of Weights and Measures. However, in other fields such as statistics as well as the social and behavioural sciences, measurements can have multiple levels, which would include nominal, ordinal, interval and ratio scales.Measurement is a cornerstone of trade, science, technology and quantitative research in many disciplines. Historically, many measurement systems existed for the varied fields of human existence to facilitate comparisons in these fields. Often these were achieved by local agreements between trading partners or collaborators. Since the 18th century, developments progressed towards unifying, widely accepted standards that resulted in the modern International System of Units (SI). This system reduces all physical measurements to a mathematical combination of seven base units. The science of measurement is pursued in the field of metrology.
1. Homework Statement
hi
i need to perform the experiment described in this link
http://www.phywe.com/index.php/fuseaction/download/lrn_file/versuchsanleitungen/P2430400/e/P2430400.pdf
so i need to measure the torque
in the experiment they use Torsion dynamometer to do the job
but i need to...
Hello everyone.
I'm working on a physics lab project and I've reached a barrier.
I need to measure the torque on a closed loop in a magetic field and I can't reach a way to do so. Of course, excluding all the torque measuring devices and such which I believe we don't have at the lab.
Any ideas...
Homework Statement
There is an air-tight 1L Canister filled with 90% water and 10% N2O. This canister is attached to some clear tubing which is not entirely air-tight. At the end of this tubing are some tungsten particles averaging ~1µm in diameter with total mass of 60mg. The contraption is...
I'm trying to create a quantum circuit which does the following very simple thing:
Alice has two qubits, and she wants to measure the observables: X⊗Z, Z⊗X, and Y⊗Y, each taking values in {-1,1}.
Note that this is a commuting set of observables, so it should be possible to measure all three...
Ever since Einstein showed us that time is relative, and that there is no such thing as independent time but a space-time fabric, and since we’ve got experimental results about the dilatation effect that speed and gravity/acceleration have on time: Is it OK to say that the universe started 13,79...
Why don't we just connect a sine wave generator in series with a DMM and the coil, set the amplitude Δv0 to a given value on a scope, measure the RMS current I on the DMM and use Z = 0.707Δv0/I?
Homework Statement
To measure the depth of a lake, an empty bottle (V=1dm^3) is lowered to the bottom of the freshwater lake. There is a weight attached to the bottom of the bottle to keep it upright. When the bottle is recovered it is filled with 0,58dm^3 of water. Determine the depth of the...
Why does measuring the position of a particle change its momentum?
Is it because 'measuring' involves shooting EM waves or other particles at the particle, which changes its momentum?
Hello all,
A bit of background. We are communicating with a microcontroller through a desktop computer. The desktop computer controls direction of rotation of the motor, and it can prompt a step in the motor causing a rotation. However, what can I do in terms of feedback? I have not taken...
Can anyone tell me if the following is correct?
Traveling directly towards a source of light at some constant speed, we will measure its frequency to be higher (compared to rest frequency) than what we would expect when using Newton’s laws. Just as traveling away from the source, we would...
Homework Statement
Hi guys, I am attempting to experimentally measure torque from two rods connected to a servo. Let's say rod A stays fixed, and the servo, mounted at the end of rod A (at joint J) moves rod B to a certain angle θ with a velocity v. In addition to velocity and angle, I also...
im hooking up 6 450v 10000uf capacitors in parallel for an exparement for school (under supervision of my professor) he won't tell me how to monitor these devices and how to know when they are full and when to release them.
does anyone think they could give me a quick and dirty answer?
A group of researchers from the University of California has published a paper regarding the viability of detecting cosmic rays using an array of 'SmartPhones'. I've read before that the digital sensors (photomultipliers?) in most cameras and cell phones detect infrared and, by design, this is...
I used a ticker to measure to measure the acceleration of falling object. And and now I am writing report about it and the problem is what symbol is used for the marks on the ticker tape? Like for grams (g). What would you use for marks(?) ?
A bicyclist applies varied force and velocity on their pedals as it goes around one revolution. The power distribution over one revolution is like two waves with the higher power being made on the downstrokes. The push through the bottom/top produces the lowest power. The question is does...
Homework Statement
I was hoping that someone would be able to help me solve this problem regarding simple functions and their measure. This problem is coming straight from *Introduction to Measure Theory* by Terrence Tao. A link to the free version is attached at the end of this post.
Show...
I was lately interested in learning how the human body weight changes through out the day. Like, how much weight (may be in just 10s of grams) is lost during sleeping, after bathing, after workout and like that.
For that I would require a highly precise scale. But most commercially available...
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Thanks for...
I’m learning about cosmology and I’m struggling understanding the size and shape of the universe.
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hey everyone, I am a chemistry student and i am currently working on my final year project, which is to find a chemical difference between canned and bottled coke. one of the aspects I am looking at is CO2 content, so i need a way of measuring the quantity of CO2 in a container.
ideally i want...
Measuring CO2
I have been searching for an answer to this for quite a while, so I'm hoping somebody here can help me out. I've spent quite a bit of time digging and reading, and I've found plenty of information, but I'm not always sure what to make of it. I am working on making myself a small...
Hello there!
I'm working for about 2 months to build a system for getting digitally values about the angle of the elbow. The project is designated to create a large usage tool and that's why it's preferably to use mechanical staff that are comfortable for the 'user' and to not look very...
Hello,
I am trying to design an experiment where I can calculate the distance at which polarization will not have a measurable effect on a neutral object, from a sphere charged by a Van Der Graaf generator. I am measuring the weight change caused by the polarization of the neutral object with...
I understand that the dynamic modulus of a material is measured by inducing a sinusoidal force and measuring the strain response. Usually one gets a value for the storage and loss modulus. However, I don't understand how one would "quantify" how viscous a material is. I know a viscous material...
Homework Statement
A spin-1/2 system in the state \left|ψ\right\rangle = \left|0.5, z\right\rangle of the S_{z} spin operator has eigenvalue s = +\hbar/2. Find the expectation values of the S_{z} and S_{x} operators.
Homework Equations
\left\langle S_{x,z}\right\rangle = \left\langle ψ...
I understand that work done if we have (510,000 Kg or 5,000,000 N) of water falling 30 meters (like in a dam) would just be 5,000,000N * 30m= 150,000,000 Newton meters.
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I am having a hard time understanding how to measure current safely in the following circuit.
The circuit consists of an isolated step up transformer. 50V 1kHz pulsed dc on the primary and 500V 1kHz pulsed dc on the secondary @ 10mA max. I am wanting to measure current on the secondary side of...
Hello PF
Let's say I have a device with three layers, A, B, and C, where layers A and C are the anode and cathode.
I can measure the IV curves from that device easily. Now let's say I added a fourth layer, D, in between A and B. Layer D interacts with layer B such that it increases it's...
Hello all,
My lab recently purchased a deformable lens, which can change its focal length from 140 mm to 40 mm and anywhere in between, based on current applied to it.
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Something that's been bugging me, but unable to find an answer for..
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Let us have an observer moving at some velocity v.
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Hi Fellas,
Need your help to solve a practical problem I've been facing.
I run a company that makes products for foundries. Recently, we started work on developing a high temperature, high emissivity ceramic coating to paint the inside walls of a furnace. The motive behind the particular...
Even as a kid, I saw beauty in old devices. That made me want to understand how they worked. I had lots of old things that I keep and now reviving. Old things need to work to see the beauty. Here's what I've done so far.
Two views of the gadgets shelves and my small work space...
I'm working on research into the feasibility of separating out the infrared rays above 1200 nm in sunlight for solar power generation. Since silicon cells do not effectively harness these wavelengths, we are experimenting with using interference coatings and a wave guide to separate these waves...
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I'm looking for a set of equation(s) to solve the following problem:
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Thank you. This is not homework, just a...
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Hi,
I would like to record a voltage on a ardruino pin A0 using the 3.3V from the arduino. I connect the 3.3V to one part and the A0 to another part. I want to know when there's contact between the two parts (resulting in 3.3V on pin A0) and when there's no contact (resulting in 0V on pin A0)...
The electric charge is measured in Coulombs.
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I'm confused by the fact that electronic charge is defined in terms of...
Hey all, first I just want to say that I am by no means a physicist - just someone that is very interested in physics, and I have very little understanding of physics, but I am trying to learn.
I've been reading this article about anisotropic synchrony convention which mentions that we cannot...
Hey.
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I read that the level of oxygen in the atmosphere reached its highest concentration during the Carboniferous period, with over 32% of the atmosphere by volume as O2. I was wondering, how is this measured?
The reference on wiki only links to a graph with no other content.
Thanks.
I have a range of sine waves I have obtained in an experiment.
I want to put a measure on the purity of these sine waves - how well the reproduce a theoretical sine wave.
Is there anyway I can analyse the FFT of the sine waves in Matlab and put a measure on the purity of the sine wave...