- #1

TeddyLu

- 8

- 0

T

_{H}= 1000 K

T

_{C1}= 200 K

T

_{C2}= 300 K

It is given that the two heat rejected are of equal value.

determine the maximum thermal efficiency.

## Homework Equations

thermal efficiency (carnot) = 1 - T

_{C}/T

_{H}= 1 - Q

_{C}/Q

_{H}

## The Attempt at a Solution

Since there was two heat sinks with an equal value of heat rejected at each:

Q

_{C1}= Q

_{C2}= Q

_{C}

therefore, Q

_{H}= Q

_{C1}+ Q

_{C2}will turn into

Q

_{H}= 2Q

_{C}

I took the entropy balance equation to solve for Q

_{C}:

0 = Q

_{H}/1000 - Q

_{C}/200 - Q

_{C}/300

but I don't have a constant on the other side to figure out for Q

_{C}to plug back in to find Q

_{H}and then solve for thermal efficiency.

any help please?