The steel and aluminum plate assembly is bolted together and fastened to the wall. each plate has a constant width in the z direction of 200 mm and thickness of 20 mm. if the density of a and b is 7.85 mg/m3 and 2.71 mg/m3 for c, determine the location of the center of mass. neglect the size and weight of the bolts.

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.