posted by Tracy .
Which one of the following statements about a thermodynamic engine is not true, i.e., which one of the statements is false?
1)The internal energy is always the same at the beginning and at the end of one cycle.
2)The absorbed and the exhausted heat have the same magnitude.
3)No engine can be more efficient than a Carnot engine.
4)The pressure is always the same at the beginning and at the end of one cycle.
5)The path in a pV-diagram is closed.