1. What force is required to punch a hole 50 mm in diameter through a 16-mm-thick aluminum-alloy plate? An average stress of 265 MPa will cause this material to shear.
2. How wide a gap should be allowed between the 50-ft-long paving slabs of concrete in a street so that the slabs will touch each other at a temperature of 90 degrees F? The pavement is laid at a temperature of 65 degrees F. What would be the compressive stress in the slabs if the temperature rose to 110 degrees F? (E for concrete is 3 000 000 psi.)
3. A wire made of copper alloy is 4.5 m long and 1 mm in diameter. It is stretched 14.5 mm by a load of 340 N. What is the modulus of elasticity of this alloy?
4. The total elongation of a square wrought iron bar 50 mm on a side and 3 m long is 1.5 mm. What is the load?
5. Find the total elongation and the stress in a 1-in-diameter AISI 1045 steel rod 12 ft long under a pull of 12 000 lb.