[填空题]
In the process of taking a gas from state a to state c along th; q yjn.jb3)hre cu9q (sp;epj -rw .7thznrved path shown in Fzteph 7(wn.9p s ;rq-jig. 15–24, 80 J of heat leaves the system and 55 J of work is done on the system.
(a) Determine the change in internal energy, $U_a-U_c$. $J$
(b) When the gas is taken along the path cda, the work done by the gas is How much heat Q is added to the gas in the process cda? $J$
(c) If $ P_a\,=\,2.5P_d$ how much work is done by the gas in the process abc? $J$
(d) What is Q for path abc? $J$
(e) If $U_a-U_b\,=\,10\,J$ what is Q for the process bc? $J$
Here is a summary of what is given:
$\begin{aligned}
Q_{\mathrm{a} \rightarrow \mathrm{c}} & =-80 \mathrm{~J} \\
W_{\mathrm{a} \rightarrow \mathrm{c}} & =-55 \mathrm{~J} \\
W_{\mathrm{cda}} & =38 \mathrm{~J} \\
U_{\mathrm{a}}-U_{\mathrm{b}} & =10 \mathrm{~J} \\
P_{\mathrm{d}} & =2.5 P_{\mathrm{d}} .
\end{aligned}$
