Nearly 1 billion people do not have access to clean, safe, drinking water. In many countries, women and children walk for hours to bring water back to their homes. The water they are able to bring is dirty and often carries disease. Identify two criteria or constraints that would apply to a possible solution for providing clean, safe water to a community.

Fluids at rest possess no flow energy. 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.

Air is compressed isentropically from an initial state of 300 k and 101 kpa to a final temperature of 1000 k. determine the final pressure using the following approaches: (a) approximate analysis (using properties at the average temperature) (b) exact analysis