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## Forces |

The commands in the Forces menu and Forces toolbar add, measure, and configure kinetostatic forces.

To calculate the forces that act on Parts, there must be a minimum of one kinematic-chain that is kinematically-defined, which has a minimum of one Part with Mass and/or Inertia* and/or there is a Spring to apply a force.

To calculate the forces correctly, you must make sure the Power flows correctly through the kinematic-chain - see Configure Power Source.

Mass Properties

Parts have three sources of Mass and Inertia*. The sources are: •Profile / Extrusions - see Extrusion > Mass Properties •User Mass Properties - see CAD-Line > Mass Properties tab > User Mass Properties •SolidWorks Mass Properties - see CAD-Line > Mass Properties tab > SOLIDWORKS Mass Properties We add together the three sources of Mass and Inertia. * the correct term for Inertia is Mass Moment of Inertia. It has SI units of . |

Note:

If a Part has Mass but does not have Inertia (Mass Moment of Inertia), it is a Point-Mass, - mass that is concentrated at a point. In reality, this is not possible (we do not model singularities or Black-Holes!) However, we allow the concept.

In reality, when a Part has Mass it must also have Inertia*. The Inertia* is a summary of how the mass in the Part is distributed around its Center-of-Mass, and where the Center-of-Mass is located in the Part.

On-line Tutorial: Tutorial 13: Forces Introduction

Forces menu (MD17)

The Force toolbar is to the right of the graphics-area.

If, after you display Force Vectors, the arrowheads of the vectors are outside of the graphics-area, you must use the Scale buttons to decrease the length of the Force Vectors and/or Torque Vectors - see Feedback Area > Vector Scaling buttons

FORCE |
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Action of its surroundings on a body tending to change its state of rest or motion. |

LINE OF ACTION OF A FORCE |

The line along which the vector that represents a given force lies. |

MAGNITUDE OF A FORCE |

Number of units of force obtained by comparing a given force with a standard, taken as unit force -(SI units : Newtons) |

ACTIVE [APPLIED] FORCE |

Force capable of producing motion. |

REACTION |

Force arising in a constraint and acting upon a constrained body due to the action of an active force upon that body. |

CENTRIPETAL FORCE |

Force causing the centripetal acceleration of a particle. |

INERTIA FORCE |

Product of the mass of a particle and the negative of its acceleration. Following D'Alembert, the inertia force can be regarded as being in equilibrium with the resultant of all the forces acting on the particle. |

CENTRIFUGAL FORCE |

Inertia force of a particle moving uniformly along a circular path. |

CORIOLIS FORCE |

Inertia force equal to the product of the mass of a particle and the negative of its Coriolis component of acceleration. |

GRAVITATIONAL FORCE |

Force equal to the product of the mass of a particle and the Gravitational Acceleration on Earth - taken as 9.806m/s/s. |

We calculate for you those Forces that result from these Accelerations :

CORIOLIS ACCELERATION |
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Component of the absolute acceleration of a point due to its velocity relative to a rotating frame of reference. It equals twice the vector product of the angular velocity of the moving frame of reference and the relative velocity of the given moving point. |

CENTRIPETAL ACCELERATION |

Acceleration of a point towards the center of curvature of its path as it moves along a fixed curve. |

TANGENTIAL ACCELERATION |

Component of acceleration of a point collinear with its velocity. |

NORMAL ACCELERATION |

Component of acceleration of a point normal to its velocity. |

ANGULAR ACCELERATION |

Rate of change of angular velocity with respect to time. |