A cylindrical specimen having a cross-section of radius, r, is subjected to a uniaxial tensile force, F, as shown in the accompanying figure. Establish a criterion for the selection of light and stiff materials for this bar (Hints: You need to develop an expression for the mass of material required in terms of tension, bar length, density, and stiffness of the material). ہے

need correct answer within 15min No need of explanation

The cable of hoist has a cross sectional of 80mm2.The hoist is used to lift a crate weighining 500 kg.The free length of of the cable is 30 m.Assume all deformation is elastic. (a) what is the stress on the cable. (b) How much will the cable extend if it is made from steel(E-200 Gpa)? (c) How much will the cable extend if it is made from polypropylene(E-1.2 Gpa)?

Q3: Two material were tested in tension, the first is aluminum alloy has stress-strain curve define by 300 MPa was fracture after 35% reduction in area. The other a copper alloy has stress-strain curve define by=100+120 MPa was fracture after 98% elongation. Which alloy have more toughness? Support your answer with the sketch.?