Classify the following processes as reversible, irreversible, or impossible. a)A
ID: 1718939 • Letter: C
Question
Classify the following processes as reversible, irreversible, or impossible.
a)A machine operating in a cycle receiving 325 kJ of energy from a 1000 K reservoir, and rejecting 125 kJ to a 400 K reservoir.A total of 200 kJ of work is produced.?
b)A machine operating in a cycle receiving 325 kJ of energy from a 1000 K reservoir and producing 0 kJ of work.
c)A refrigeration system receiving 400 kJ of energy from a 400 K reservoir, having a work input of 300 kJ, and then rejecting 800 kJ of energy to a 1000 K reservoir.
Explanation / Answer
A)
Max efficieny = 1- TL/TH=1-325/1000= 0.675
Real efficieny)=W/Qh = 200/325=0.615
irreversible
b)
Max efficieny = 1- Tl/th= 1-325/400= 0.1875
Real efficieny)=W/Qh =0/325=0
imposible
c)
Max efficieny = 1- Tl/th=1- 400/1000 = 0.6
Real efficieny)=W/Qh =300/800= 0.3
irreversible