A cylindrical metal specimen 12.7 mm (0.5 in.) in diameter and 250 mm (10 in.) long is to be subjected to a tensile stress of 28 MPa (4000 psi); at this stress level, the resulting deformation will be totally elastic. a. If the elongation must be less than 0.080 mm (3.2 x 10^-3 in.), which of the metals are suitable candidates? Why?
b. If, in addition, the maximum permissible diameter decrease is 1.2 x 10^ -3 mm (4.7 x 10^-5 in.) when the tensile stress of 28 MPa is applied, which of the metals that satisfy the criterion in part (a) are suitable candidates? Why?

Consider a power plant with water as the working fluid that operates on an ideal rankine cycle. it has a net power output of 45mw. superheated steam enters the turbine at 7mpa and 500°c (h=3411.4 kj/kg; s=6.8 kj/kg k) and is cooled in the condenser at a pressure of 10 kpa by running cooling water from a lake through the tubes of the condenser at a rate of 2000 kg/s. (a) show the cycle on a t-s diagram (a right schematic is fine - you do not need to calculate the temperatures at each point); (b)-determine the work done by the turbine and the pump in kj/kg; (c)-the mass flow rate of water used by the power plant; (d)-the thermal efficiency of the cycle; (e)-the temperature rise of the cooling water. assume the cooling water is incompressible with cp 4.18 kj/kg°c.