Assignment#1

1. In 1989, Jason, a research-type submersible with remote TV monitoring capabilities and weighing 35 200 N, was lowered to a depth of 646 m in an effort to send back to the attending surface vessel photographs of a sunken Roman ship offshore from Italy. The submersible was lowered at the end of a hollow steel cable having an area of 452 × 10–6 m2 and E= 200 GPa. Determine the extension of the steel cable. Due to the small volume of the entire system, buoyancy may be neglected. (Note: Jason was the system that took the first photographs of the sunken Titanic in 1986.) weight of steel per unit volume is 77 kN/m3.

2. Two prismatic bars are rigidly fastened together and support a vertical load of 45 kN, as shown in Figure. The upper bar is steel having length 10 m and cross-sectional area 60 cm2. The lower bar is brass having length 6 m and cross-sectional area 50 cm2. For steel E = 200 GPa, for brass E = 100 GPa. Determine the maximum stress in each material. Specific weights of brass and steel are 84kN and 77kN.

3. A 70 kN compressive load is applied to a 5 cm diameter, 3 cm tall, steel cylinder. Calculate stress, strain, and deflection.

4. What tensile stress is required to produce a strain of 8×10−5 in aluminum? Report the answer in MPa. Aluminum has a Young’s modulus of E = 70 GPa.

5. Stress-strain curves for materials in compression differ from those in tension. Explain.

Quiz#1

•Chapter 1 and 2 –SOM by R. S. Khurmi •Assignment#1