What is Solid: Definition and 1000 Discussions

In object-oriented computer programming, SOLID is a mnemonic acronym for five design principles intended to make software designs more understandable, flexible, and maintainable. The principles are a subset of many principles promoted by American software engineer and instructor Robert C. Martin, first introduced in his 2000 paper Design Principles and Design Patterns.The SOLID concepts are

The Single-responsibility principle: "There should never be more than one reason for a class to change." In other words, every class should have only one responsibility.
The Open–closed principle: "Software entities ... should be open for extension, but closed for modification."
The Liskov substitution principle: "Functions that use pointers or references to base classes must be able to use objects of derived classes without knowing it". See also design by contract.
The Interface segregation principle: "Many client-specific interfaces are better than one general-purpose interface."
The Dependency inversion principle: "Depend upon abstractions, [not] concretions."The SOLID acronym was introduced later, around 2004, by Michael Feathers.Although the SOLID principles apply to any object-oriented design, they can also form a core philosophy for methodologies such as agile development or adaptive software development.

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  1. B

    Volume of solid x^2 + (y-1)^2 =1 about y-axis

    Homework Statement Hello, I am to find the volume of the solid given by x2 + (y-1)2=1 rotated about the y-axis. I may use either shells or cylindrical method. I attempted shell method, but am just learning this, still foggy and this is the one question that isn't coming out right. Homework...
  2. A

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  3. A

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  4. C

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  5. H

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  6. M

    If the earth's core was to abruptly turn solid

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  7. M

    Using shell method to find the volume of a solid

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  8. S

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  9. ZetaOfThree

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  10. kelvin490

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  11. J

    Smells from Solid Matter: Wood

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  12. Hardik Batra

    Discover the Derivation of Solid Angle: Short and Simple Method

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  13. I

    What Is the Most Current Model in Solid State Physics?

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  14. duhuhu

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  15. S

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  16. Q

    Help I'm feeling stupid. :( ("A solid sphere rolls down an incline)

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  17. jjrocks

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  18. duhuhu

    Glued Versus Solid Model in Modal Analysis

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  19. N

    Angular velocity of a solid disk

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  20. N

    Laser Beam - Divergence and Solid Angle

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  21. T

    Solid Introductory Text to Ordinary Differential Equations

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  22. S

    MHB Solid by rotating a region

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  23. andyrk

    Time for falling down the incline (Rotating Solid Cylinder)

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  24. R

    Negating the need for anything actually solid

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  25. K

    MHB Volume of Solid of Revolution; Simpson's Rule

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  26. adjacent

    Why NaCl does not conduct electricity in solid state?

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  27. tridianprime

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  28. G

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  29. T

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  30. R

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  31. T

    Solid Mechanics Stress Blocks- Principle blocks

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  32. T

    Simply Supported Beam Stress Block Selection

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  33. M

    X-ray applications in solid state physics

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  34. M

    Is Delta H of formation the same for NH4NO3 Aqueous and in Solid Form?

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  35. veronica1999

    MHB Volume of Solid with Circular Base & Equilateral Triangles

    A solid has a circular base of radius 3. If every plane cross section perpendicular to the x-axis is an equilateral triangle, then it's volume is I keep on getting 18 root 3. But the answer is 36 root 3. Could I get some help? Thanks.
  36. I

    Use a double integral to find the volume of the indicated solid

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  37. R

    Steel Soap bars: magnetic core, solid?

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  38. G

    Solid pivoted pendulum attached to a spring - oscillation period?

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  39. B

    Regarding Kittel's solid state physics 167 page

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  40. D

    Diffraction condition - Kittel's Intro to Solid State Physics 8th ed.

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  41. Z

    Angular momentum of a solid cylinder rotating around axis

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  42. K

    Can a Torus Be Created with Checkerboard Quadrilateral Faces?

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  43. N

    Entropy of a mole of a crystalline solid as a function of temperature

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  44. S

    Kinetic Energy of Rotating Solid disk or cylinder about symmetry axis

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  45. A

    MHB Find the volume of the solid of revolution, or state that it does not exist. #2

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  46. A

    MHB Find the volume of the solid of revolution, or state that it does not exist.

    Find the volume of the solid of revolution, or state that it does not exist. The region bounded by f(x)= the square root of ((x+3)/(x^3)) and the x-axis on the interval [1,infinity) is revolved around the x-axis. I tried using the disk method: pi* (sqrt(((x+3)/(x^3)))^2 Then I think I have to...
  47. Y

    Introduction level Solid State - Mean free time/path & lattice spacing

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  48. O

    Atoms in a Solid: Why Their Vicinity Matters

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  49. T

    Volume of a solid using disks/washers

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  50. S

    Brushed motor solid magnet strength

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