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Areheat rankine cycle operates with water as the working fluid. steam enters the first turbine at 8 mpa and 450°c and exits at 0.8 mpa. it is then reheated to 400°c before entering the second turbine, where it exits at 10 kpa. if the amount of work into the pump is 8.04 kj/kg and the net work per cycle produced is 1410.25 kj/kg, determine the thermal efficiency of the cycle.

An inventor claims to have developed a reversed heat engine (ie. a heat pump) which is able to deliver 10 kj heat into the room at 20°c from outside ambient temperature of -10°c by consuming only 2 kj electricity in winter. this claim is a)-impossible b)-possible only if the heat pump is ideal c)-practically possible d)-unable to be assessed as it depends on the working fluid used in the heat pump.

Consider a beam traveling through diamond and impinging upon the diamond-air interface. the critical angle of incidence for total internal reflection to occur is closest to the following value: select one: a)-22.50° b)-23.85 c)-24.30 d)-23.40° e)-none of the above