General

[quote=SoloZX]imma assume there's no curve from B to C. So coefficient of performance is Q/W

heat from A ->B :
pressure is constant so work done by system = p delta v
delta u = Q - p delta v, delta u = 4.0kj (B = 5 a = 1), P delta v = 4.0kj
Q = 4 + 4 = 8.0Kj

heat from C -> A
volume is constant so delta u = heat added, so basically you added 1.0 - 0.2 which is 0.8kj of heat

that's all the heat you added.

work = p delta v
its basically a triangle because you have 3points A,B, and C
so height (10 - 2) x length (5 -1) /2 = 16 bar L = 1.6kJ

COP = Q/W = (8.0+0.8)/1.6 = 5.50[/quote]

THANK YOU SO MUCH! That was how to do it. Sorry for the late response, had minor plans. I was able to contact my professor and have it extended. You assumed correctly, there was no curve or anything. I really appreciate the help, I needed it. But now that makes perfect sense how to do it.

Im sorry but I am only in High School.

Bleh I'm taking my second thermo course, I could solve it but I don't feel like it.

Lovely wall of random letters and numbers.

Anyways, you should email your professor (if you are in college). Other than that, I can't really help much.

I'm just gonna take a whack at it.

Coefficient of Performance=Q/W
W=PV
COP=(A+B+C)/3
COP=(1/(10*1)+5/(10*5)+0.2/(2*1))/3
COP=0.10

Don't count on me for the answer. Just guessing.

@radkai: Then it could be that OP is taking a college course that covers the stuff not covered in AP Chemistry/Physics. Let us just admit that neither of us have a clue as to how to solve the problem.

[quote=radkai]I have never learned a thing called coefficient of performance.[/quote]
That's because you're in high school.

Maybe this will help.

http://en.wikipedia.org/wiki/Coefficient_of_performance

EDIT: Super Mega Ultra Ninja'd

@KevinKiri: Not just that, my courses won't do it. I covered thermodynamics in physics already and now it's all electromagnetism till summer vacation. Chemistry definitely won't do engine stuff.

[quote=radkai]I have never learned a thing called coefficient of performance.[/quote]

I suppose that your course(s) did not get to it yet either. http://en.wikipedia.org/wiki/Coefficient_of_performance

[quote=KevinKiri]"At state A: U = 1.0 kJ, P = 10.0 bar, V = 1.0 L

At state B: U = 5.0 kJ, P = 10.0 bar, V = 5.0 L

At state C: U = 0.2 kJ, P = 2.0 bar, V = 1.0 L

IMPORTANT: Provide your answer to the nearest hundredth of a digit.

The cycle runs as a heat cycle. [b]What is the coefficient of performance?[/b]"

To those that have no idea what he is asking...read more carefully?

OT: I have no idea. Not getting into thermodynamics for another month or so.[/quote]

I have never learned a thing called coefficient of performance.

"At state A: U = 1.0 kJ, P = 10.0 bar, V = 1.0 L

At state B: U = 5.0 kJ, P = 10.0 bar, V = 5.0 L

At state C: U = 0.2 kJ, P = 2.0 bar, V = 1.0 L

IMPORTANT: Provide your answer to the nearest hundredth of a digit.

The cycle runs as a heat cycle. [b]What is the coefficient of performance?[/b]"

To those that have no idea what he is asking...read more carefully?

OT: I have no idea. Not getting into thermodynamics for another month or so.

haven't done physics in ages! assuming you're from america, why not ask help on yahoo answers or on a student forum? it may help to go onto www.thestudentroom.co.uk as they give awesome homework help too

Taking AP Chemistry and AP Physics B concurrently, I still have no idea what this stuff is.

you can't email your professor/ask someone in your dorm/text or call your professor or anyone in your class?

P.S. i have no idea what you're asking

i know some of these words