Measuring Definition and 1000 Threads

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.

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  1. A

    I Measuring electron spin and measuring entangled electron spin

    Hi people, Lets assume, we have a stern gerlach setup and we are going to measure an atom's last orbit electron's spin with 60 degree from vertical axis. Therefore, in this case, our outcomes would be 3/4 for spin up, 1/4 for spin down. Let's assume, we have the same setup but we are going to...
  2. K

    Measuring the Speed of Sound in Water, Using Faraday's Law

    Hi! This project involves both mechanical and electrical elements, so I'm discussing it in this forum since I'm not sure which one it would fit better into. I'm working on an experiment in which I'm trying to measure the speed of sound through water. The approach is simple: I have a long...
  3. P

    I Measuring Low Resistance: Why Meter Bridge is the Preferred Choice

    Why meter bridge is chosen over post office box to measure low resistance?
  4. Al-Layth

    I Measuring the Velocities of Astronomical Objects in the Milky Way

    I am looking for the most relied upon studies that measured the motions of the sun, earth, jupiter...etc any or all of the various astronomical objects in the milky way galaxy. Particularly interested in the orbital velocities of the planets
  5. abdulbadii

    Measuring thermal conductivity of a metal

    What'd be practical method and/or portable, simple tool (like sort of electricians' multimeter) to meter the heat conductive constant of a metal?
  6. H

    Probabilities of measuring ##\pm \hbar/2## along ##\hat{n}##?

    Hi, Given a spin in the state ##|z + \rangle##, i.e., pointing up along the z-axis what are the probabilities of measuring ##\pm \hbar/2## along ##\hat{n}##? My problem is that I'm not sure to understand the statement. It seems like I have to find the probabilities of measuring an eigenvalue...
  7. S

    Engineering Measuring rotational speed for Tachometer vs Oscilloscope

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  8. M

    Measuring wavelength of microwave radiation using double slits

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  9. C

    I Ways of measuring open quantum systems

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  10. Richard90

    Finding an Equation for Measuring Reactive Force at the Gastrocnemius

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  11. L

    I Measuring Model Rocket Velocity: Is it Possible?

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  12. A

    I Measuring the rotation curve of galaxies

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  13. Hereweald

    B Curious about this proposition for measuring for FTL

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  14. String theory guy

    Why Measure the Center of Mass from the Same Position After a Collision?

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  15. earthling75

    Stuck calculating probability of measuring ##S_y## for spin 1 particle

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  16. B

    A Quantum projection when measuring state population

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  17. A

    RC Circuits: Measuring Capacitance

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  18. squeekymouse

    B How to understand the steradians equation for measuring a sphere of light?

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  19. kma

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  20. Talal

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  21. K

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  22. Wrichik Basu

    What is the correct way of measuring remaining battery capacity?

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  23. Astronuc

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  24. flying_bear

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  25. Mayan Fung

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  26. PhysicsTest

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  27. E

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  28. N

    A Constructing the Wigner Function from Measurements of Entangled Photons

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  29. TheSpectacularSpecs

    I Surface Differential Rotation by measuring the position of sunspots

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  30. Yan Campo

    I Probability when measuring a local observable

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  31. N

    Medical Error measuring glucose optical sensor

    Hello We have designed an optical sensor to measure glucose. But we do not have the same changes for different concentrations. What do we need to do to be able to observe different Lifetime concentrations? In our sensor test, we used phosphorescence and glucose oxidase technology. The sensor...
  32. iochoa2016

    I Measuring characteristic impedance as suggested by KRAUS' book

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  33. J

    Why isn't the scaling factor included when stating particle mass in eV?

    not technically a homework question, just figured it fit here.
  34. mastermechanic

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    Hello everyone, Nowadays I am planning to redesign my centrifugal compressor which I designed for a subsystem in my graduation project. It's a 3D printed and brushless motor driven centrifugal compressor and its about a hand size. However, due to its relatively small size and relatively low RPM...
  35. alan123hk

    B Measuring Light's Brightness & Power Flux Relative to Observer's Speed

    Assuming that the observer moves along the direction of the light, does the speed of the observer's measuring instrument relative to the light source (which may be close to the speed of light) affect the brightness and/or power flux density measured by the observer? I'm not sure about this...
  36. ARoyC

    Measuring Capacitance using a basic Multimeter

    Is there any way to measure the capacitance of a capacitor indirectly using a multimeter that does not have the option to measure capacitance directly?
  37. C

    I What is this formula measuring error?

    Variance and standard deviation and other measures of error I understand. This formula doesn't behave well for data sets centered around zero and also has other problems, like scaling differently as N increases than the standard deviation or standard error. Does anyone recognize this and can...
  38. C

    B Measuring change in g with height (TV program many years ago)

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  39. B

    A Measuring new forces with molecular vibrations

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  40. T

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  41. Sciencemaster

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  42. kimiko333

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  43. Ebi Rogha

    I Measuring Photon Intrinsic Nature: Is Interference a Factor?

    I would like to know, how can we be sure this is not due to the influence/impact/interference of our measurement, not necessarily the intrinsic nature of photons? In most reference books, it seems it is a given and it is not discussed
  44. sophiecentaur

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  45. MikeandSuch

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  46. Marioweee

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  47. C

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  48. T

    Measuring high velocity airflow

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  49. qnach

    Automotive How Can You Measure Wood Plate Thickness from One Side?

    I have access to only one side of the plate, i.e. cannot clamp both sides of the plate to measure. Is there any way, perhaps acoustic methods, to measure a plate thickness from only one side?
  50. brainbaby

    Measuring ripple reduction in LTSpice

    Dear friends, I am simulating a capacitance multiplier circuit and an RC filter circuit simultaneously. My aim is to check the reduction in ripples when using a cap multiplier circuit against an RC filter. I am familiar with ltspice but not quite an expert. I am comparing two output waveforms...
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