Designing an energy attenuation system that controls the 1200 kg car traveling at 100 km/hr at impact. Compare to design an energy attenuation system that controls the energy of a car at a fast speed.

The mass flow rate of the fluid remains constant in all steady flow process. a)- true b)- false

The higher the astm grain size number, the finer the gran is. a)-true b)-false

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.