What is Statics: Definition and 902 Discussions

Statics is the branch of mechanics that is concerned with the analysis of (force and torque, or "moment") acting on physical systems that do not experience an acceleration (a=0), but rather, are in static equilibrium with their environment. The application of Newton's second law to a system gives:






F


=
m


a



.


{\displaystyle {\textbf {F}}=m{\textbf {a}}\,.}
Where bold font indicates a vector that has magnitude and direction.





F




{\displaystyle {\textbf {F}}}
is the total of the forces acting on the system,



m


{\displaystyle m}
is the mass of the system and





a




{\displaystyle {\textbf {a}}}
is the acceleration of the system. The summation of forces will give the direction and the magnitude of the acceleration and will be inversely proportional to the mass. The assumption of static equilibrium of





a




{\displaystyle {\textbf {a}}}
= 0 leads to:






F


=
0

.


{\displaystyle {\textbf {F}}=0\,.}
The summation of forces, one of which might be unknown, allows that unknown to be found. So when in static equilibrium, the acceleration of the system is zero and the system is either at rest, or its center of mass moves at constant velocity. Likewise the application of the assumption of zero acceleration to the summation of moments acting on the system leads to:






M


=
I
α
=
0

.


{\displaystyle {\textbf {M}}=I\alpha =0\,.}
Here,





M




{\displaystyle {\textbf {M}}}
is the summation of all moments acting on the system,



I


{\displaystyle I}
is the moment of inertia of the mass and



α


{\displaystyle \alpha }
= 0 the angular acceleration of the system, which when assumed to be zero leads to:






M


=
0

.


{\displaystyle {\textbf {M}}=0\,.}
The summation of moments, one of which might be unknown, allows that unknown to be found.
These two equations together, can be applied to solve for as many as two loads (forces and moments) acting on the system.
From Newton's first law, this implies that the net force and net torque on every part of the system is zero. The net forces equaling zero is known as the first condition for equilibrium, and the net torque equaling zero is known as the second condition for equilibrium. See statically indeterminate.
A physicist who does research in statics is called a statician.

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  1. J

    I Does mass density affect load distribution on barbell?

    Had an argument with a few guys at the gym today. I told them that loading a barbell with 100 on each side instead of 2 45s and a 10 causes more pressure on your spine. This example is in reference to someone performing a low bar squat in which the bar has contact points across the entire back...
  2. C

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    Hello, I've been studying for the FE, and this question in the Statics section of the review I am going through has really tripped me up for some reason. I understand Statics, and how to determine forces in X and Y directions, determining X and Y components using trig, etc, etc.. Maybe I am...
  3. JasonR2

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    Question: Three forces of magnitude 45 kN, 24 kN and 12 kN are applied to the truss connection as shown. Knowing that the connection is in equilibrium, determine the magnitude of the forces C and T. Equations: Fx = 0 Fy = 0 My attempt: Fx=0: -24kN + Tcos40 + Csin20 = 0 Fy = 0: 45kN +...
  4. P

    Determine the mass moment of inertia of the assembly

    Homework Statement Determine the location of y of the center of mass G of the assembly and then calculate the moment of inertia about an axis perpendicular to the page and passing through G. The block has a mass of 3 kg and the mass of the semicylinder is 5 kg. Homework Equations -parallel...
  5. RoboNerd

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  6. RoboNerd

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  7. U

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  8. F

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  9. ramzerimar

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  10. Halest0rm3

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  11. P

    Moment of inertia avoid double integral?

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  12. goonking

    Solving 3D Statics Homework with Free Body Diagram

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  13. P

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  14. goonking

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  15. goonking

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  16. c1tonsoup

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  17. N

    Statics: Crane Boom - Why Different Results?

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  18. N

    Finding Internal Loadings on a Cantilevered Beam

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  19. faradayscat

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  20. P

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  21. P

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  22. W

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  23. B

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  24. S

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  25. P

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  26. CaptainAtom1996

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  27. Z

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  28. S

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  29. S

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  30. AdamMcParland

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  31. D

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  32. Lito

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  33. W

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  34. D

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  35. W

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  36. W

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  37. J

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  38. D

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  39. M

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  40. W

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  41. W

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  42. I

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  43. Gian Lukmana

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  44. V

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  45. A

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  46. red1312

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  47. W

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  48. A

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  49. A

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  50. K

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