CIVE 210 Exam 1 with Solution, Fall 2011

CIVE210 — Fall 2011-12 Quiz 1 M. Mabsout & A. El-Souri Problem I: (30 points) (2° Tick Boxes to check that you solved all questions \ The cable system (AB and AC) is used to support the forces shown in Figures J-a and I-b. 1. Referring to Figure I-a, let 6=60° and 0,=30°. If a tensile force of 50 N is measured in cable AB, calculate P; for P}=200 N and P=100 N. What is the force in cable AC. (8 points) Calculate the force in cable AC if P2=200 N while P; is kept at 200 N. Comment briefly on the result. (7 points) . yy t a ‘ 2 LP Calculations and/or Diagrams: _-Ab--egasshiluiuoan : cone cee eee eee cece eee eee cee eeeeee oath Sy Oe Ee a ec ee 5 Rens: 40.2. MOD Sia B2..2.8g. 4 Fae La = 0 cocenecenececneeneenceceeneneeee 2, = FO 199.80. GO_-=10Q. Sinda_k Fae SiMdT occ —. Sgn l22e OL fon i ~ " 0 CIVE210 — Fall 2011-J2 Quiz 1 _M. Mabsout & A. El-Souri Calculations and/or Diagrams (cont'd): ger Cos 6 Om Ets. SOUL = AOS GO.3.0. 2 Lecce eree enero CIVE210 — Fall 20] 1-12 Quiz | M. Mabsout & A. El-Souri 2. The system is modified with three springs of stiffness k;k:=k3=1,000 N/m and initial length 1p=0.2 m for all springs, as shown in Figure I-b. The final lengths of the springs, ze after the forces are applied, have been measured as 1;=0.25 m, 1=0.15 m, and 1;=0.4 m. Calculate the forces in cables AB and AC. (15 points) Calculations and Diagrams: Rak [AW ak (h 8 = 50M. LL) Bc Kaladd ak {tas taba 970M AGE Ry Gaal be [ly nf a tre fh CIVE210 — Fall 201]-12 Quiz 1 M. Mabsout & A. El-Souri Problem I: (15 points) L CLT EL LL LIA Vw) The cords (or cables) suspend the buckets at A and B in the equilibrium position shown in wy A. Figure Il. If the weight of the bucket at B is 40 Ibs, determine the weight of the bucket at (15 points) Calculations and/or Diagrams: Se tt.._-E CIVE210 — Fall 2011-12 Quiz I M. Mabsout & A. El-Souri Problem II: (25 points) 4it = Bit 7 3ft 1 2 wx Figure IT An elliptical ring lying in the horizontal plane (X,Y) is supported by three cables AB, AC, and AD, as shown in Figure Il]. The equation of the ellipse for the ring is given as: ma (X/ay + (W/b)? = 1 where a=1.5 and b=3. Determine the forces in the cables if the ring has a weight of 50 Ibs. (25 points) Calculations and/or Diagrams: Quiz 1 M. Mabsout & A. El-Souri CIVE210 — Fall 2011-12 Calculations and/or Diagrams (cont’d): 7 _ room AB =. OBR Cx 2S = n~ a — Bagg = ONE AOTS yn 0.Bb Ie a i Ann CIVE210 — Fall 2011-12 Quiz 1 M. Mabsout & A. El-Souri Problem IV: (20 points) (> Figure TV Referring to Figure IV, determine the moments of the force vector F about the x, y, and z axes. Solve the problem using: (a) a Cartesian vector approach and (b) a Scalar approach. Express ize each result as a Cartesian vector. (14 points) Determine the moment of the force vector F about an axis extending between points A and C. yw Express the result as a Cartesian vector. (6 points) Calculations and/or Diagrams: CIVE210 — Fall 2011-12 Quiz 1 M. Mabsout & A. El-Souri Calculations and/or Diagrams (cont'd): hee = BOR eet) 0 Seen ne SY eee. ve Ek ree CIVE210 — Fall 2011-12 Quiz 1 M. Mabsout & A. El-Souri Problem V: (/0 points) Three couples are applied to the bent bar shown in Figure V. Determine the vector components of the resultant moment about x, y, and z, and express as a Cartesian vector. (10 points) (Hint: This a 5 mn question maximum. Take advantage of the notion of couples) Calculations and/or Diagrams: