1. **State the problem:** We have a reversible no-flow process where the work done is $-156.2$ kJ, initial volume $V_1 = 0.845$ m³, and pressure varies with volume as $p = -730V + 690$ kPa. We need to find the final volume $V_2$.
2. **Formula for work in a reversible process:** Work done is the area under the $p$-$V$ curve, given by
$$W = \int_{V_1}^{V_2} p \, dV$$
3. **Substitute the pressure relation:**
$$W = \int_{V_1}^{V_2} (-730V + 690) \, dV$$
4. **Integrate:**
$$W = \left[-730 \frac{V^2}{2} + 690V \right]_{V_1}^{V_2} = \left[-365V^2 + 690V \right]_{V_1}^{V_2}$$
5. **Apply limits:**
$$W = (-365V_2^2 + 690V_2) - (-365V_1^2 + 690V_1)$$
6. **Plug in known values:**
$$-156.2 = (-365V_2^2 + 690V_2) - (-365(0.845)^2 + 690(0.845))$$
Calculate the known term:
$$-365(0.845)^2 + 690(0.845) = -365 \times 0.714025 + 583.05 = -260.62 + 583.05 = 322.43$$
7. **Rewrite equation:**
$$-156.2 = (-365V_2^2 + 690V_2) - 322.43$$
Add $322.43$ to both sides:
$$-156.2 + 322.43 = -365V_2^2 + 690V_2$$
$$166.23 = -365V_2^2 + 690V_2$$
8. **Rearrange to standard quadratic form:**
$$-365V_2^2 + 690V_2 - 166.23 = 0$$
Multiply both sides by $\cancel{-1}$:
$$\cancel{-}365V_2^2 + \cancel{-}690V_2 + \cancel{-}166.23 = 0$$
$$365V_2^2 - 690V_2 + 166.23 = 0$$
9. **Solve quadratic equation:**
Use quadratic formula:
$$V_2 = \frac{690 \pm \sqrt{(-690)^2 - 4 \times 365 \times 166.23}}{2 \times 365}$$
Calculate discriminant:
$$690^2 = 476100$$
$$4 \times 365 \times 166.23 = 242638.2$$
$$\sqrt{476100 - 242638.2} = \sqrt{233461.8} = 483.22$$
10. **Calculate roots:**
$$V_2 = \frac{690 \pm 483.22}{730}$$
Two possible values:
$$V_2 = \frac{690 + 483.22}{730} = \frac{1173.22}{730} = 1.606$$
$$V_2 = \frac{690 - 483.22}{730} = \frac{206.78}{730} = 0.283$$
11. **Interpretation:** Since $V_1 = 0.845$ m³ and work is negative (work done by the system), volume likely decreases, so
**Final answer:**
$$V_2 = 0.283 \text{ m}^3$$
Work Volume 5Afcab
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