Question Three a) A wire 3m long and 2mm in diameter when stretched by weight of 10kg has its length increased by 0.28mm. Find the stress, strain and Young Modulus of the material of the wire. (g = 9.81m/s²) b) A steel column is 3.5m long and 0.4m diameter. It carries a load of 50MN. Given that the modulus of elasticity is 200GPa, calculate the compressive stress and strain, and determine how much the column is compressed.

A solid steel bar 250 mm long is 10 mm square over part of its length, the remainder being circular with a diameter of 25 mm. A gradually applied tensile load P kN induces maximum stress in the bar of 200 MPa. The total strain energy in the bar when this stress of 200 MPa  is acting is 1,3 Joule. Take E = 200 GPa   Calculate : The load The length of the square portion of the bar The load that falls from a height of 8 mm and induces 1,3 Joules in the bar

2. A core made of stainless steel (material 1, E, = 28 Msi) is fully bonded to an inner shell of brass (material 2, E, = 15 Msi), which is fully bonded to an outer shell of aluminum (material 3, Ea = 10 Msi). The rod is subjected to a compressive load, P = 50 kips. Determine: a) the normal stress in the brass and b) the deflection of the composite rod. Dimensions: L = 10 in, dı = 1 in, d2 = 2 in, d3 = 3 in. Recall that Msi =10° psi. Ans: ob = 7.76 ksi (C), ô = 5.176 x 10-³ in (shorter) 3 2 1 d, d d, - P