Statics Review of statics 1. The basic concepts and the difference between them (The difference between a resultant R and the principal vector R: Resultant force R is the sum of the translational effect of the principal vector and the rotational effect of the principal moment(principal vector and principal moment reduce to a resultant force). (It depends on the point of application Principal vector R'only causes only a translational effect Additionally a principal moment may exist. (it does not depend on the point of application 2The difference between a force moment and a force couple moment Force moment is the moment of a force about a point, it depends on the center point. Thereby, it can not be transferred arbitrarily in a plane an Force couple moment can be transfered freely in the plane or in another plane which is parallel to the plane. It does not depend on the center point3 1. The basic concepts and the difference between them: ①The difference between a resultant R and the principal vector R'. Resultant force R is the sum of the translational effect of the principal vector and the rotational effect of the principal moment (principal vector and principal moment reduce to a resultant force). (It depends on the point of application) Principal vector R' only causes only a translational effect. Additionally a principal moment may exist. (it does not depend on the point of application) ②The difference between a force moment and a force couple moment Force moment is the moment of a force about a point, it depends on the center point. Thereby, it can not be transferred arbitrarily in a plane. Force couple moment can be transfered freely in the plane or in another plane which is parallel to the plane. It does not depend on the center point. Review of Statics