- #1

ts547

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## Homework Statement

A 200 litre container of boiling water and a 200 litre container of ice cold water are used

as heat source and sink for a Carnot engine. Calculate the maximum amount of useful

work that can be obtained from the system and the final temperature of the two

containers of water.

## Homework Equations

W=Q_h-Q_c

W=(1-T_c/T_h)*Q_h

Q=nC(T2-T1)?

## The Attempt at a Solution

Im getting mega confused. I thought the carnot engine was a cyclic process i.e the temperatures of the resevoirs don't change. For example the heat energy transfers are during isothermal expansions in the reservoirs so I get

W=nR(T_h-T_c)ln(V_2/V_1)

but we don't know one of the V's. Does a 200 litre container imply that it's full? In that case the heat transfer would have to come from an isochoric process as the container is a fixed volume. That would make sense in order to find the temperature change but that's the second part of the Q. Otherwise the max work out would be when the log term is max but that is infinity.

Can you find Q_h from knowing just the temperatures and volumes of the reservoirs? That would solve all my problems. Well, its a start...

Thanks for your help in advance