Solid Definition and 1000 Threads

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. M

    Angular and CoM Velocities of a Solid Sphere

    Homework Statement A solid sphere of mass M and radius R is rolling,without slipping, down a curved rail. The sphere is initially at rest at a height of h1. Find the angular velocity ω2 and the center of mass velocity of the sphere vcm at the end of the rail of height h2. You may assume that...
  2. A

    Do I need to know Solid State Physics for Field Theory?

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  3. M

    Can covalent bonds in water break by pushing them on a solid?

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  4. B

    Varying Volume Charge Density in a Solid Cylinder

    Homework Statement Consider a right circular cylinder with radius R and height L oriented along the z-axis. The center of the cylinder coincides with the origin. Inside the cylinder the volume charge density is given by \rho(z)=\rho_0+\beta z. Find the electric field at the origin (in terms...
  5. P

    Calculating Volume of Solid Using Triple Integral

    1. Use a triple integral to find the volume of the given solid. The solid enclosed by the cylinder x^2 + z^2 = 4 and the planes y = -1 and y + z = 4 This looked like a cylindrical coordinate system to me, except for the fact that it is not cylindrical around the z-axis but the y-axis. I...
  6. R

    Wave Propagation in Vibrating Solid

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  7. M

    Work, energy stored in solid sphere

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  8. F

    Can a solid planet become a star?

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  9. N

    Calculating Volume of Described Solid with Equilateral Cross-Sections

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  10. W

    Describing a Solid Ice Cream Cone with Spherical Coordinates

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  11. T

    Archived Solid State Physics: Hall Effect + Semiconductor Lab

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  12. N

    Why amino acids as Zwitterons in solid state and ph neutral?

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  13. MarkFL

    MHB Solid of revolution about an oblique axis of rotation

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  14. Feodalherren

    Volume of a solid using shells

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  15. Z

    Derivative of Solid Angle: Lightmann & al. Explained

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  16. I

    Thermodynamics: Einstein solid (simple step in derivation)

    S=kln(\frac{eq}{N})N --->= S=Nkln(\frac{q}{N}+1) i understand that the e goes away and the N exponent comes down but where does the +1 come from?
  17. L

    MHB Find volume of solid generated (Calc 2)

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  18. A

    Nitpicky details of solid body motion

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  19. MarkFL

    MHB Forrest's question at Yahoo Answers regarding a solid of revolution

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  20. S

    Magnetic moment of a solid, uniformly charged ball

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  21. S

    Centre of mass of a solid hemisphere (Feynman way)

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  22. N

    Can KNO3 and bentonite clay increase rocket engine performance?

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  23. MarkFL

    MHB Bassman's question at Yahoo Answers regarding a solid of revolution

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  24. Y

    Electric Field with a Solid Spherical Conductor

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  25. andyrk

    Charged Spherical Shell and Solid Sphere

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  26. I

    Using double integration in finding volume of solid bounded by curves?

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  27. MarkFL

    MHB Belinda Obeng's question at Yahoo Answers regarding a solid of revolution

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  28. S

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  29. MarkFL

    MHB Panda Bear's question at Yahoo Answers regarding solid of revolution

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  30. C

    Is this a solid way to mark an exam on a Mathematical subject?

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  31. P

    Drawing schematics for solid state physics research

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  32. K

    Confusing Solid And Plane Angles

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  33. K

    Rolling resistance of solid tires versus pneumatic

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  34. K

    MHB The volume of the solid generated by the revolution

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  35. karush

    MHB What is the volume of the solid formed using the shell method?

    https://www.physicsforums.com/attachments/1012 Let f(x)=\sqrt{x}, Line L is the normal to the graph of f and point (4,2) (a) show that the equation of L is y=-4x+18 f'=\frac{1}{2\sqrt{x}} so f'(4)=\frac{1}{4} so normal would be -4 then L is y-2=-4(x-4) or y= -4x+18 (b) Point A is the...
  36. E

    Solid Fuel Internal Combustion Engine

    Has anyone ever built an internal combustion engine which runs on solid fuel? A system would have to use waste heat or a mechanical friction device or whatever to heat the fuel and produce vapor which would be burnt in the cylinder (similar to the way coal gas was produced). Of course the vapor...
  37. MarkFL

    MHB Huzafa's question at Yahoo Answers regarding a solid of revolution

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  38. I

    How Does Electron Diffusion Create the Depletion Region in Solid State Devices?

    how does letting the electrons diffuse to the P material/region lead to a "depletion" region in the center where the N and P material meet? please go into detail
  39. A

    Is Pressure Important in Thermodynamics of Solid Materials?

    Hi. Consider a solid body placed in vacuum. How much is its pressure? Can we describe this body using thermodynamics if its pressure is zero?
  40. A

    Solid pulley & mass on an inclined plane

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  41. PhizKid

    Field due to a solid hemisphere with uniform charge density

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  42. C

    Why/how does integral of solid angle = pi?

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  43. G

    Enthelpy under uniaxial compression of solid

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  44. A

    Help with interference fits of sleeve on a solid shaft

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  45. M

    Effects on water level when a sphere is replaced by a new solid sphere

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  46. L

    Question about instantaneous travel of information on a solid

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  47. E

    Is it possible to excite solid metal using radioactive material?

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  48. J

    Not understanding what the question is asking. Volume of solid

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  49. R

    MHB Find the volume of the solid obtained by rotating the area?

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  50. MarkFL

    MHB Amanda's question at Yahoo Answers regarding a solid of revolution

    Here is the question: Here is a link to the question: Calculus homework help? - Yahoo! Answers I have posted a link there to this topic so the OP can find my response.
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