Statics Introduction Force system: coplanar force system or three-dimensional x无法显 force system C planar (coplanar system of concurrent forces force 2coplanar system of parallel forces(coplanar system: system of force couples is a special cast general case of a force system in a plane Special kast of force system in a plane: coplanar system bf concurrent forces, coplanar system of force couples and coplanar system df parallel forces Coplanar system of concurrent forces: Example: the Forces whose lines of action intersect at one hook ofla crane point are called concurrent, if all the concurrent forces acting on a body lie in one plane - the form a coplanar system of concurrent forces The methods of study: the graphical method 72 and the analytical method 33 Coplanar system of concurrent forces: Forces whose lines of action intersect at one point are called concurrent, if all the concurrent forces acting on a body lie in one plane, they form a coplanar system of concurrent forces. Introduction ①coplanar system of concurrent forces ②coplanar system of parallel forces (coplanar system of force couples is a special cast) ③general case of a force system in a plane The methods of study: the graphical method and the analytical method. Example: the hook of a crane Force system: coplanar force system or three-dimensional force system Coplanar force system: Special cast of force system in a plane: coplanar system of concurrent forces, coplanar system of force couples and coplanar system of parallel forces