What is quantities: Definition and 207 Discussions

Quantity or amount is a property that can exist as a multitude or magnitude, which illustrate discontinuity and continuity. Quantities can be compared in terms of "more", "less", or "equal", or by assigning a numerical value multiple of a unit of measurement. Mass, time, distance, heat, and angle are among the familiar examples of quantitative properties.
Quantity is among the basic classes of things along with quality, substance, change, and relation. Some quantities are such by their inner nature (as number), while others function as states (properties, dimensions, attributes) of things such as heavy and light, long and short, broad and narrow, small and great, or much and little.
Under the name of multitude comes what is discontinuous and discrete and divisible ultimately into indivisibles, such as: army, fleet, flock, government, company, party, people, mess (military), chorus, crowd, and number; all which are cases of collective nouns. Under the name of magnitude comes what is continuous and unified and divisible only into smaller divisibles, such as: matter, mass, energy, liquid, material—all cases of non-collective nouns.
Along with analyzing its nature and classification, the issues of quantity involve such closely related topics as dimensionality, equality, proportion, the measurements of quantities, the units of measurements, number and numbering systems, the types of numbers and their relations to each other as numerical ratios.

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  1. N

    Which one of the quantities below has dimensions equal to ML/T^2?

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  2. Z

    Why are no DIVERGENT quantities (infinities) in String Theory ?

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  3. S

    Radiometric Quantities: Physics of EM Wave Explained

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  4. S

    Confusion over real and complex versions of the same quantities

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  5. B

    Mixing three water quantities at different temperatures

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  6. fluidistic

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  7. fluidistic

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  8. A

    Solving Quantities and Units Homework as an Access Student

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  9. Q

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  10. S

    Formulating Physical Quantities, Energy & Conservation of Energy

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  11. Char. Limit

    Vector Quantities: Can Unit of Measurement Reveal Vector?

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  12. M

    Galilean invariance and conserved quantities

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  13. M

    Vector Quantities in word 2007

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  14. S

    Sites where I can purchase small quantities of components?

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  15. E

    Physical Meaning of Mathematical Quantities

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  16. B

    Quantities describing time-dependent phenomena measurable initially?

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  17. R

    Are Current, Potential, and Potential Difference Scalar or Vector Quantities?

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  18. O

    Humans emit very small quantities of light

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  19. M

    Feel of physical quantities - help

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  20. D

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  21. S

    Problems converting quantities

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  22. Goddar

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  23. T

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  24. M

    So, what is the deal with differentials and infinitesimals in physics?

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  25. M

    Why would large quantities of dark matter not stick together ?

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  26. Peeter

    Conserved Quantities from Boost/Rotation of Maxwell Lagrangian

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  27. Q

    Differential geometry in quantum mechanics - conserved quantities

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  28. B

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  29. D

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  30. M

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  31. L

    How do i find quantities in fusion formulae

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  32. M

    Fourier series technique to show that the following series sum to the quantities

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  33. A

    Conserved Quantities in de Sitter ST

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  34. H

    Infinitely many integrable/conserved quantities? Soliton?

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  35. P

    Symmetries and conserved quantities

    I know that if a particle is in a spherically symetric potential its angular momentum will be conserved, but what about if somehow we manage to produce say an elliptically symmetric potential? Will the particle then have a momentum along the curve of the ellipse conserved? Thanks
  36. B

    Invariance of combinations of physical quantities

    Please tell me if there are motivated physical reasons to consider that combinations of dimensionless physical quantities that appear at the exponent of e in distribution functions have the same magnitude in all inertial reference frames in relative motion, Thanks in advance
  37. L

    What are the differences between scalar and vector quantities?

    Hmm... I don't know the differences between the scalar and vector quantities? Help, please? I don't want to fail physics!
  38. 0

    Why dimensions can be treated as algebraic quantities?

    Hi, in my physics book (serway) they say "dimensions can be treated as algebraic quantities" but I don't understand this very well. If I sum meters I get meters, if I multiply meters I think I get meters^2 because the area of a rectangle is b.h. But if, for instance, I multiply seconds.seconds...
  39. V

    Why are Planck quantities so extreme?

    Why are Planck quantities considered to be maximum and minimum quantities - Planck distance etc ? If they are,then,since in calculus a maximim/minimum is given by,for example,dy/dx = 0,then,for example,y = Planck quantity when x = some other quantity.But what is x?
  40. R

    Understanding Vector and Scalar Quantities in Physics

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  41. E

    What does quantities and dimensions mean?

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  42. Mentz114

    Invariant quantities in the EM field

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  43. M

    Linear & Angular Quantities

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  44. A

    Invariant quantities for antimatter

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  45. P

    Quantities as an ordinary decimal number

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  46. M

    Potential conserved quantities

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  47. I

    Vector Addition of differing quantities

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  48. A

    How Do You Calculate the Mass of Water Produced in a Chemical Reaction?

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  49. F

    Number of basic physical quantities

    Recently, I was thinking about this: Am I right if I say that there are only 4 (and exactly 4) basic physical quantities which are enough to explain all observed phenomena in nature? (of course I mean HOW, not why) (for example length, time, mass and electric charge or current)...
  50. S

    Definition of 4-vector quantities

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