Is the 'Semicircle' in the PV Diagram Actually a Semi Ellipse?

[issacnewton]

Hi

I have question about the problem statement, I am posting it here. The problem statement says "semicircle" in a P-V diagram. But it seems to be a semi ellipse. Is that the sloppy
statement in the problem ?

 

[tiny-tim]

hi IssacNewton!

yes you're right, it's a semi-ellipse

i suppose they're trying to say that it's quadratic, and the curve is vertical at A and B

 

[issacnewton]

Thanks tiny-tim. Happy belated new year