REVIEW INNOVATIONS NOVEMBER 2021 CE BOARD EXAM ALVAREZ 1 INSTRUCTION: Select the correct answer for each of the following questions. Mark only one answer for each item by shading the box corresponding to the letter of your choice on the answer sheet provided STRICTLY NO ERASURES ALLOWED. GOOD LUCK. NOTE: A times B is represented by AxB or A*B. A raised to the power n is expressed as A*n. All problems are 1 point each. Situation 1. As shown in Figure MEC-101, a weight W hangs from two wires each with cross-sectional area of 113 mm, If € = 30° anda = 45°, 1. Find the largest weight, W (KN), that can be carried by the wires if the maximum stress in the wires is not to exceed 124 MPa. A. 19.14 c. 16.91 B. 15.62 D. 22.04 2. If the weight W = 25 KN, what is the resulting stress in wire AC (MPa)? A. 161.96 c. 198.35) B. 114.52 D. 188.28 3. If the weight W = 25 KN, determine the required cross-sectional are mm) of the wires so that the max stress does not exceed 124 MPa. aA. 148 c. 105 B. 182 D. 127 (sa. Situation 2. The two 200-N blocks, shown in Figure MEC-102, are pushed apart by the 15° wedge of negligible weight. The angle of static friction is 12° at all contact surfaces. 4, Determine the reaction (in N) between the wedge and the block if the block starts moving. A. 47.6 c. 229.3 B. 53.5 D. 48.6 5. Determine the reaction (in N) between the block and the floor if the block starts moving. A. 47.6 c. 229.3 B. 53.5 D. 48.6 6. Determine the force P (in N) required to start the blocks moving. A. 47.6 c. 229.3 B. 53.5 D. 48.6 Situation 3. As shown in Figure MEC-103, the mast hinged at B was used to lift ‘the load W. Neglect the weight of the mast. Given: msm mdm H=9m 7. What is the resultant force (in kN) at B if W = 24 kN? A. 36.0 c. 39.4 B. 20.0 D. 16.0 8. What is the tensile force (in kN) in the cable AC if W = 48 KN? A. 20.0 c. 22.3 B. 87.3 D. 40.0 Page TofSREVIEW INNOVATIONS ALVAREZ 1 - CE Board November 2021 9. What is the biggest load W (in KN) that can be lifted if the maximum tensile force in the cable AC is 50 kN and the mast weighs 8 kN? A. 64.0 c. 60.0 B. 50.0 D. 56.0 Situation 4. The water supply pipe shown in Figure MEC-104 is suspended from a cable using a series of close and equally spaced hangers. The length of the pipe supported by the cable is 60 m. The total weight of the pipe filled with water is 6.5 kN/m. 10. What ie the maximum sag (in m) at the lowest point of the cable which occurs at mid length if the allowable tensile load in the cable is 2550 kn? A. 0.87 ce. 1.15 B. 0.77 D. 1.30 11. The sag of the cable at mid-length is 3 m. Find the maximum axial stress (in MPa) if the cable diameter is 75 mm. a. 177 c. 44 B. 252 D. 225 12. The sag of the cable at mid length is 2m. If the allowable tensile load in the cable is 2000 KN, how mich additional load (in kN/m) can the cable carry? A. 8.82 ¢. 15.3 B. 2.31 D. 6.50 Situation 5. A xight-angled rigid pipe is fixed to a wall at A and is additionally supported through the cable CD as shown Figure MEC-105. The tension in the cable is 3 kN 13. Neglecting the weight of the pipe, which of the following most nearly gives the largest shear force (in kN) on the pipe’s cross section? A. 3.00 ©. 2.71 B. 1.28 D. 2.97 14. Neglecting the weight of the pipe, which of the following most nearly gives the maximum bending moment (in kN-m) at A? A. 2.72 c. 4.88 B. 3.47 D. 2.31 15. Neglecting the weight of the pipe, which of the following most nearly gives the maximum twisting moment (in kN-m) about x-axis? A. 1.90 c. 0.53 B. 0.84 D. 0.79 Page 2 ofSREVIEW INNOVATIONS ALVAREZ 1 - CE Board November 2021 [ \i Figure MEC-102 Figure MEC-101 Speco RL menage 2 Figure MEC-103 W= 6.5 Ki/m Figure MEC-104 Figure MEC-105 ~o00~ Nothing Follows Page 30f3