試題詳解

9. A gas in a cylinder starts from initial state i to finial state f through 4 different paths as shown in the figure. Regarding to the heat energy, work, and internal energy, which statements is incorrect?

(A) Path 1 is isobaric expansion, gas must be heated.
(B) Path 2 is isothermal expansion； no work is involved in this process.
(C) Path 3 is adiabatic expansion, therefore no heat transfer occurred.
(D) Path 4 is isochoric cooling； heat is extracted out of gas.
(E) Gas do not do work for path 4 only.