Tutorial 5 Properties of Lines, Areas and Volume EME1016 Applied Statics Tri.1_2018/2019 Tutorial-5 (Properties of Lines, Areas and Volume) (1) Locate the centroid ( x, y ) of the shaded area shown below: Ans. :A( x, y =1.13m, 3.6m) Ans. : B( x, y = (5a)/8, (2ka)/5) Ans. : C( x, y = 3b/4, 3h/10) Ans. : D( x, y =4a/3 , 4b/3 ) 1 Tutorial 5 Properties of Lines, Areas and Volume (2) EME1016 Applied Statics Tri.1_2018/2019 For the uniform wires bent in the figures shown below, Locate: (a)- the centroid ( x & y ), of Fig.A (b)- the centroid ( x , y , z ), of Fig.B Ans.: A ( x, y =24.4mm , 40.6mm) (3) Ans. :B( x , y , z = 0.074m,, 0.037m,, 0 .157m) For the member’s cross-sectional areas shown below; Locate: (a)- the centroid ( x & y ), of the cross-sectional area, Fig.A, (b)- the centroid ( x & y ), of the angle’s cross-sectional area, Fig.B. Ans.: A ( x, y = 2.73m, 1.42m) Ans.: B ( x, y =77.2mm, 31.7mm) 2 Tutorial 5 Properties of Lines, Areas and Volume (4) EME1016 Applied Statics Tri.1_2018/2019 For the beam’s cross-sectional areas shown below; (a)- Determine the distance ( y ), the centroid then Find the moment of inertia (Īx`) about the x` - axis, (b)- Determine the moment of inertia ( I x & I y ) about the x & y -axes. Ans. :( y =170.0mm, and Īx`, Īx , Īy=722(106) mm4, 2.17(103) mm4, 91.7(106) mm4) (5) Determine the volume and the total surface of the body shown below; Ans.: (V = 255x103mm3) 3 Tutorial 5 Properties of Lines, Areas and Volume (6) EME1016 Applied Statics Tri.1_2018/2019 Locate centroid y of the paraboloid. Ans. :( y =2.67m) (7) For the cross-sectional area of the T-beam, (a)Determine y , which locates the centroidal axis x` for the cross-sectional area of the Tbeam, (b) Find the moments of inertia Īx` about x` - axis. Ans. : ( y =48.25mm and Īx` =15.1x106mm4) 4 Tutorial 5 Properties of Lines, Areas and Volume (8) EME1016 Applied Statics Tri.1_2018/2019 The king’s chamber of the Great Pyramid of Giza is located at its centroid. Assuming the pyramid to be a solid, prove that this point is at Z = ¼ h, suggestion: Use a rectangular differential plate element having a thickness dz and area (2x)(2y). Ans. :( Z =h/4) 5 Tutorial 5 Properties of Lines, Areas and Volume (9) EME1016 Applied Statics Tri.1_2018/2019 Determine the moments of inertia, Īx and Īy of the beam’s cross-sectional area about x and y- axis. Ans. : (Īx = 115X106 mm4; Īy =153X106 mm4) 6