A composite plane wall consists of a 5-in.-thick layer of insulation (ks = 0.029 Btu/h*ft*°R) and a 0.75-in.-thick layer of siding (ks = 0.058 Btu/h*ft*°R). The inner temperature of the insulation is 67°F. The outer temperature of the siding is -8°F.

Determine at steady state:

(a) the temperature at the interface of the two layers, in °F, and (b) the rate of heat transfer through the wall in Btu/h*ft^2 of surface area.

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Asimple rankine cycle uses water as the working fluid. the water enters the turbine at 10 mpa and 480c while the condenser operates at 6 kpa. if the turbine has an isentropic efficiency of 80 percent while the pump has an isentropic efficiency of 70 percent determine the thermal efficiency

What is creep? what is stress relaxation?