What is Measurements: Definition and 394 Discussions

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. 7

    Can Magnetic Field Strength Decrease with Distance in Plasmas?

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  2. G

    Discover the Truth About Weak Measurements in 2007 | Postbiota Discussion Thread

    http://postbiota.org/pipermail/tt/2007-May/000515.html Does anyone know what happened with these experiments?
  3. O

    Local measurements on an entangled pair. (My understanding)

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  4. T

    Engineering 101: Understanding One Meter (1 m) & Weight Measurements

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  5. M

    Advantages of Radian Measurements

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  6. H

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  7. R

    G from cosmological measurements

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  8. Loren Booda

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  9. C

    Can operators describe a single or many measurements simultaneously?

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  10. R

    Measuring Time Intervals: How Precise Can We Go?

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  11. T

    Why Does the Measurement Problem Terrify Physicists?

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  12. M

    Weak measurements? Modified Double slit

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  13. Simfish

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  14. G

    Uncertainty/errors in meter stick measurements

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  15. H

    Measurements on YBCO, and their meaning.

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  16. H

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  17. L

    Looking for introduction on QND: quantum non-demolition measurements

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  18. O

    Significant figures when taking measurements.

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  19. T

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  20. J

    Question about Measurements and sig. figs.

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  21. E

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  22. S

    Is My Calculation of Uncertainty in Measurements Correct?

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  23. L

    Is the QM axiom for measurements misleading?

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  24. E

    Do EPR Tests Require Simultaneous Measurements?

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  25. S

    What Are the New Insights from Bs - Anti-Bs Mixing Measurements at Fermilab?

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  26. B

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  27. D

    What is the projection postulate in quantum mechanics?

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  28. O

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  29. A

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  30. S

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  31. S

    Calculate a spring constant using measurements from a Hooke's Law

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  32. bayan

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  33. P

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  34. A

    Calculating Filling Time for a Large Bottle of Water

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  35. J

    Measurements of time/distance be dependent on an object's velocity

    I'm just starting to learn about relativty, and I'm having trouble understanding it. Maybe someone could help? The first thing that I'm have trouble grasping is why would measurements of time/distance be dependent on an object's velocity relative to the speed of light?
  36. F

    Lasers in Measurements: Learn How to Use Them

    Hi! I have to make a presentation about the usage of lasers in measurements, but I am not sure what I should include. I thought of something like using laser beams for measuring distances, but I don't know how exactly this can be done and what else can be measured with lasers. I'd be greatful if...
  37. Z

    Is there a site to do conversions of measurements

    Is there a site that teaches how to do conversions of measurments. More specificly I need one that teaches coversion between different measurements like gallons to cubic inches or square feet to millimeters or grams to meters LOL if there is such a thing lol
  38. C

    Problem involving relative measurements

    Hello all I need help with the following problem: Two measuring sticks use the same unit but the scale on one stick has 635 marks per unit and the scale on the other stick has 465 marks per unit. Suppose the sticks are placed together so that the 0 mark on each scale line up. What is the...
  39. C

    Fluid Mechanics - Pressure measurements

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  40. B

    I need clarification about Bell state Measurements

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  41. M

    Solving Vector Addition Without Angle Measurements

    In class today we had a brief lesson on vector addition. I understand how to calculate the resultant when given a magnitude and angle measurent for each vector, but my teacher gave me no other examples. I have tons of homework problems that do not give me this information, but I am expected to...
  42. N

    Area Measurements: Converting Feet to Sq. Feet for Horse Stall

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  43. T

    Half life measurements on foams

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  44. A

    What is the correct method for combining systematic errors in measurements?

    Say you have two measurements of the same quantity: t = 500 +- 20 +- 3 t = 600 +- 90 +- 10 where the first error is statistical and the second is systematic. What is the correct way of combining the systematic errors? i.e., if I want to put both measurements together into t = x +-...
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