Aswimmer extends his wet arms into the windy air outside at 1 atm, 5°c, 50 percent relative humidity, and 30 km/h. if the average skin temperature is 25°c, determine the rate at which water evaporates from both arms and the corresponding rate of heat transfer via evaporation. the arm can be modeled as a 0.6-m-long and 7.5-cm-diameter cylinder with adiabatic ends.

Heat is added to a piston-cylinder device filled with 2 kg of air to raise its temperature 400 c from an initial temperature of t1 27 cand pressure of pi 1 mpa. the process is isobaric process. find a)-the final pressure p2 b)-the heat transfer to the air.

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

An ideal otto cycle with air as the working fluid has a compression ratio of 8. the minimum and maximum temperatures in the cycle are 300 k and 1340 k. use constant specific heats at room temperature to determine (a) the amount of heat transferred to the air during the heat- addition kj/kg, (b) the thermal efficiency, and (c) the thermal efficiency of a carnot cycle ope limits. process, in rating between the same temperature