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EE Board October 1996 Determine the outside diameter of a hollow steel tube that will carry a tensile load of 500 kN at a stress of 140 MPa. Assume the wall thickness to be’one-tenth of the oistside diameter. EE Board April 2003 ‘An elevator weighs 1000 pounds and is supported by a 5/16 inch diameter cable, 1500 feet long. When the elevator carries a 1500 Ib, the. cable elongates 6 inches more. What is the modulus of elasticity of the cable? Problem: Determine the diameter of a steel rod that will carry a tensile load of 50,000 kg at a stress of 1400 kg per square centimeter. Problem: - ‘An iron column of annular cross-section has an outer diameter of 200 mm and is subjected to a force of 75 KN. Find the thickness of the wall if the allowable compressive stress is 10 MPa. Problem: From the figure as shown, determine the stress in psi at the top surface of the second cylinder. Assume the specific weight of the material is 460 tort. Problem: Determine the maximum thickness of metal plate in which a 7.5 om diameter hole can be punched, if the plate has an ultimate shearing strength of 4245 kg per square centimeter and the punch can exert a maximum force of 200 metric tons. EE Board March 1998 The allowable tensile stress for % -20 bolt of a thread length 7/32 in. is 30,000 psi. The allowable shear stress of the material. is 15,000 psi. Where and how will such a bolt be most likely to fall? Note: Assume threads are perfectly triangular and that the force is carried at the mean thread height. At the thread due to shear Problem: A single bolt is used to lap joint two steel bars together. Tensile force on the bar is 20,000 N. Determine the diameter of the bolt required if the allowable shearing stress on it is 70 MPa. 412.4mm 8.87 x 10" psi 6.74 om 12.75 mm 20cm 19mm Problem: Determine the force required to punch a % inch hole on a 3/8 thick plate ifthe ultimate shearing strength of the plate is 50,000 psi 23,562:Ibs EE Board October 1996 What is the stress c in a thin-walled spherical shell of diameter D and a wall thickness t when subjected to an intemal pressure p? o= pD/4t Problem: AA thin hollow’sphere of radius 300 mm and thickness 2.5 m is subjected to an internal pressure. Determine the internal pressure if the tensile stress of an element in the sphere is 360 kPa 6 kPa EE Board October 1990 Awater reservoir of 24 m high and 12 m in diameter is to be completely filed with water, find the minimum thickness of the reservoir plating if the stress is limited to 50 MPa. 28mm Board April 1996 A cylindrical water tank is 8 m in diameter and 12 m high. If the tank is, to be completely filled, determine the minimum thickness of the tank plating if the stress is limited to 40 MPa. 114.77 mm EE Board April 1995 ana undora atc heedet Tomatwasrie’ © Nat MATES F8EEM 55 A, Problem: A cylindrical pressure tank is made from a metal plate whose thickness 's.20 mm. The tank has an outside diameter of 500 mm and a length of 3m. Find the maximum intemal pressure that can be applied in the tank if the stress in the metal plate is limited to 150 MPa. 12 MPa EE Board October 1996 A steel wire is 4.0 m long and 2 mm jin diameter. How much. is it elongated by a suspended body of mass 20 kg? Young's modulus for steel is 196,000 MPa. ‘s wns 8 4.274 mm Problem: From the . figure as shown, determine the total elongation of the composite body carrying a tensile load of 5 kN. Assume Ey = 10 MPa and Ez = 15 MPa. 418mm Problem: - A 30-m long aluminum bar is subjected to a tensile stress of 175 MPa, Determine the elongation if E = 69116 MPa. 76mm Problem: Assteel wire is 6.0 m long hanging vertically, supports a load of 2000 N. Neglecting the weight of the wire, determine the required diameter if the stress is not to exceed 140 MPa and the total elongation is not to 4 exceed 4.0 mm, Assume modulus of elasticity E = 200,000 MPa 4.26 mm Problem: . Determine the load capacity in kN on a 25 mm diameter x 1200 mm long steel shaft if its maximum elongation shall not exceed 1 mm. Assume E = 200,000 MPa. 81.8 KN EE Board April 1995 An iron steam pipe is 200 ft long at °C, What will be its increase in fength when heated to 100°C? Coefficient of linear expansion is 10 x 10° per °C. 0.20 ft . EE Board April 2003 A steel railroad rails 10 m long are Iéid with clearance of 3 mm at a temperature of 15°C. At what temperature will the rails just touch? If there were no initial clearance Assume: alpha = 11.7 micro m /m deg.C and E = 200 GPa 40.64 deg EE Board April 1996 A cylinder of diameter1.0 cm at 30°C is to be slide into a hole ona steel plate. The hole has a diameter of 0.99970 om at 30°C. To what temperature the plate must be heated? Coefficient of linear expansion for steel is 1.2 x 10° per °C. 56°C