Understanding Internal Energy: Path Dependence and Point Functions

[Amith2006]

Sir,
I have a doubt. The internal energy U is a unique function of any state because change in U ___________. I think the answer is internal energy U is a unique function of any state because change in U does not depend upon path.U is a point function. But the given in book is " U depends upon path". Please clear this doubt.

 

[siddharth]

You're absolutely right.

The change in the internal energy depends only on the inital and final states and does not depend on the path.

Also, the internal energy isn't even a unique function of the state properties. We can never measure the absolute internal energy of a state. We can only measure the changes in internal energy. So the question is doubly wrong.

What book are you using? I'm suprised that there is such an apalling error.

 

[Amith2006]

Sir,
I am using a book prescribed for engineering entrance. I feel it may be useful for my GRE Physics exam. Though some of the answers may be wrong, I get so many questions from it. Thank you for your help Sir.