assallamualaikum w.b.t to Dr Asnizam Abu Bakar...this is my second reflection journal...several week ago i learnt about thermodynamics...the first chapter that i learnt was second law of thermodynamics..in this chapter i learnt new things about heat engines,refrigerators and heat pumps and the carnot cycle...we must have high level of understanding..even though i do many exercise my understanding was not enough...after that i learnt about entropy...the most difficult chapter i want to understand...in this chapter, the first thing that we must know was is exactly entropy....unfortunately according to yunus a cengel in his book...he said that they cannot give an adequate answer to this question...this term "enrtropy" was same with energy...i also learnt about entropy change of pure subtances, liquids n solid and enropy change in ideal gas....to find entropy change they have their own formula that we must remember..then i learnt about isentropic...the thing that i understand in isentropic was the enropy change was equal to zero...that mean the si=s2....isentropic also means adiabatic and reversible...after that i learnt about isentopic efficiencies of steady flow devices such as turbines, compressors and pumps...to answer question that related with this subtopics we must know how to sketch the T-s diagram to illustrate what happen during the process....finally i learnt about entropy balance...the most important thing i learnt in this subtopic was to find Sgen to determine if the process was impossible or not...thank you that all know...assallamualaikum...
