Air is used as the working fluid in a simple ideal brayton cycle that has a pressure ratio of 12, a compressor inlet temperature of 300 k, and a turbine inlet temperature of 1000 k. determine the required mass flow rate of air for a net power output of 70 mw, assuming both the compressor and the turbine have an isentropic efficiency of (a) 100% and (b) 85%. assume constant specific heats at room temperature.

If a particle moves along a path such that r : (3 sin t) m and ? : 2t rad, where t is in seconds. what is the particle's acceleration in m/s in 4 seconds? a)- 16.43 b)- 16.29 c)- 15.21 d)- 13.79

During a steady flow process, the change of energy with respect to time is zero. 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.