Properties of typical rigid body:Rigid rectangle 。G a Unit mass Y constant, Sides a,b Centre of Mass XG a/2, yG b/2 Total Mass m yab, a2+b2 a3b ab3 Moment of Inertia J=m =Y 12 12 土水2程学脱
Properties of typical rigid body: Rigid rectangle
Properties of typical rigid body:Rigid triangle For a right triangle Unit mass Y constant, Sides a,b Centre of Mass xG a/3,yG =b/3 Total Mass m yab/2, a2+b2 a3b+ab3 Moment of Inertia J=m 18 =Y 36 目 土本2程学院
Properties of typical rigid body: Rigid triangle
Properties of typical rigid body:Rigid Oval When a =b=D =2R the oval is a circle a Unit mass y constant, Axes a,b Centre of Mass XG-YG=0 元ab Total Mass m=Y- 4 L2 L3 Moment of Inertia J=m12 =m 12 目 土本程李悦
Properties of typical rigid body: Rigid Oval
EOM of Rigid body Assemblages: Usually,it is much easier to use D'Alembert's principle and include inertia forces in the free-body diagram. Examples massless p(t) mass =m2 3L/4 massless A 0 mass =m c与 城 m m L L 目 土水2程学院
EOM of Rigid body Assemblages: • Usually, it is much easier to use D’Alembert’s principle and include inertia forces in the free-body diagram. • Examples
,）=xY0(0 u(x.t)=x(r) massless eL p(t) mass =m L/4 8 (b) 3U4 massless 1/4 A 0 mass m P() 自k 肠 128 人 i L m2(U4)6 16 0 (a) 1k3L/4)8 cL2)8 m1(LU2)8 (c) 目 土本程李悦