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ADAMSON UNIVERSITY CHEMICAL ENGINEERING DEPARTMENT

CHEMICAL ENGINEERING COURSE INTEGRATION 1 STRENGTH OF MATERIALS 1. A steel rod on bridge must be made to with a pull of 5000 lbs. Find the diameter of the rod assuming a factor of safety of 5 and ultimate stress of 64,000 psi.

a. 0.75 in b. 0.71 in c. 0.84 in d. 0.79 in 2. Two prismatic bars are rigidly fastened together and hanging vertically, support a vertical load of 10,000 lb. The upper bar is steel having a specific wt. 0.283 lb/in 2, length 35ft, and cross section 10in2. The lower bar is brass having a specific wt of 0.3 lb/in 2, length 20ft, and cross section 8in 2. Determine the maximum stress in steel and brass.

a. 1176 & 1322 psi b. 1176 & 1480 psi c. 1322 & 1480 psi d. none of these 3. If the ultimate shear strength of a steel plate is 42,000 psi, what force is necessary to punch a 0.75-in diameter hole in a 0.625 in thick plate?

a. 61,850 lb b. 63,000 lb c. 66,800 lb d. 68,080 lb 4. Compute the safe wall thickness of a 76.2 cm diameter steel tank. The tank is subjected to 7.33 MPa pressure and the steel material has a yield stress of 215.4 MPa. The factor of safety to use is 3.

a. 1.5cm b. 2.98cm c. 3.89cm d. 4.29cm 5. A cylindrical water tank is 8m in diameter and 12m high. If the tank is to be completely filled, determine the minimum thickness of the tank plating if the stress is limited to 40MPa.

a. 10.25mm b. 11.77mm c. 12.6mm d. 13.18mm

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6. A solid shaft 48.2cm long is used for transmission of mechanical power at a rate of 37 kW running at 1760rpm. The stress is 8.13MPa. Calculate the diameter.

a. 30mm b. 35mm c. 40mm d. 50mm 7. A hollow shaft has an inner diameter of 0.035m and an outer diameter of 0.06m. Compute the torque if the stress is not to exceed 120MPa.

a. 4100 N-m b. 4150 N-m c. 4300 N-m d. 4500 N-m 8. A steel wire 10m long hanging vertically support a tensile load of 2000N. Neglecting the weight of the wire, determine the required diameter if the stress is not to exceed 140MPa and the total elongation is not to exceed 5mm. Assume E=200GPa

a. 3.05mm b. 3.55mm c. 4.26mm d. 5.05mm 9. A steel bar 50mm in diameter and 2m long is surrounded by a shell of cast iron 5mm thick. Compute the load that will compress the combined bar a total of 1mm in the length of 2m. For steel, E=200GPa, and for cast iron, E=100GPa.

a. 196.3 kN b. 207.4 kN c. 218.6 kN d. 239.5 kN 10. Steel railroad rails 10m long are laid with a clearance of 3mm at a temp of 15°C. What is the gap between the railroad rails when the temperature is 30 °C? Coefficient of thermal expansion α = 11.7x10 -6 /°C.

a. 1.24mm b. 1.55mm c. 1.76mm d. 1.97mm 11. A steel rod with a cross sectional area of 150mm2 is stretched between two fixed points. The tensile load at 20 °C is 5000N. At what temp will the stress be zero? Assume α=11.7x10-6 /°C and E=200GPa.

a. 30.4 °C b. 34.2 °C c. 37.1 °C d. 40 °C

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12. A steel marine propeller is to transmit 45 MW at 1800 rpm without exceeding a shearing stress of 50MPa or twisting through more than 1° in a length of 25 diameters. Compute the proper diameter if G=83GPa.

a. 290 mm b. 348 mm c. 390 mm d. 448 mm 13. Determine the maximum shearing stress in a helical steel spring compose of 20 turns of 20mm diameter wire on a mean radius of 80mm when the spring is supporting a load of 2 kN.

a. 100.6MPa b. 110.6MPa c. 120.6MPa d. 130.6Mpa 14. A flanged bolt coupling consists of 8 – 20mm diameter bolt spaced evenly around a bolt circle 300mm in diameter. Determine the torque capacity of the coupling if the allowable shearing stress of the bolt is 40MPa.

a. 12.2 kN-m b. 15.1 kN-m c. 18.5 kN-m d. 22.5 kN-m 15. A flanged bolt coupling consist of 6 - 10mm diameter bolt spaced evenly around a bolt circle 300mm in diameter, and 4 - 10mm diameter bolt spaced evenly around a bolt circle 200mm in diameter. Determine the torque capacity of the coupling if the allowable shearing stress of bolt is 60MPa

a. 4.8 kN-m b. 5.5 kN-m c. 6.2 kN-m d. 10 kN-m 16. A simply supported beam, 10m long carries a uniformly distributed load of 20kN/m. What is the value of the maximum shear of the beam due to this load?

a. 100 kN b. 200 kN c. 250 kN d. 150 kN 17. A cantilever beam 6m in length carries a load that varies uniformly from 0 at the free and to 1000 N/m at the wall. What is the value of the maximum moment due to this load?

a. 3000 N-m b. 4000 N-m c. 5000 N-m d. 6000 N-m 18. A cantilever beam 3m long is subjected to a uniformly distributed load of 30 kN/m. The allowable stress in either compression or tension

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is 150MPa. If the cross-section is to be rectangular, determine the height if the height is to be twice as great as the width.

a. 110.5 mm b. 165.5 mm c. 221 mm d. 331 mm 19. A high strength steel band saw, 20 mm wide by 0.8 mm thick, runs over pulley 600 mm diameter. Determine the maximum flexural stress developed. Assume E=200GPa.

a. 266.67 Mpa b. 300 MPa c. 333.33 Mpa d. 400 MPa