Actually I have two questions.
- we know the efficiency of heat engine equal {1-(t/T)},where t is sink temperature and T is source temperature. Now, if two source and one sink reservior are connected by a heat engine(as shown in picture),then if T is taken as sum of two source temperature and that gives wrong answer.
From picture, t=200 and T=800+400=1200 ,so efficiency is {1-(200/1200)} give wrong answer.
why do we need to find individually? But also adding up two individual efficiency give wrong answer(100% up efficiency).
If i take heat (from picture Qa+Qb) and work(net work divided by total heat supplied) instead of temperature then it gives me right answer.
- why does the use of heat give me right answer?