Question

a reservoir heat engine operates with an efficiency of 50℅ during each cycle,it rejects 150 cal to a reservoir of heat at 30°C . then,a) what is the temp of other reservoir b)how much work does it carry out per cycle

Answer 1

Sol;-

C ( efficiency ) = 50% = 0.5

Q2 = 150

Q1 = ?

C = 1 - Q2 / Q1

1/2 = 1- 150 / Q1

So , Q = 300 cal

Now we know , 

Delta Q = Delta E + W

Where Delta E is zero in cylic process

Delta Q = W

Q2 - Q1 = 150- 300 = - 150 cal

And temp of reservior is :-

C = 1 - T2 / T1

1/2 = 1 - 303 / T1

T1 = 606 k