Statics Force system: a group of forces acting on a body Balanced force system: if a body subjected to a A force system is in equilibrium state, /F we call the system to be a balanced 2. Rigid body a body which does not change its shape and dimension under applied forces is called a rigid body 3. Equilibrium state a body is called to be in the state of equilibrium if it does not move or if it moves with an uniform velocity11 Force system: a group of forces acting on a body. Balanced force system: if a body subjected to a force system is in equilibrium state, we call the system to be a balanced. A body is called to be in the state of equilibrium if it does not move or if it moves with an uniform velocity. 2.Rigid body A body which does not change its shape and dimension under applied forces is called a rigid body 3.Equilibrium state A F