95 A sample of gas expands from V=1.0 m and pP1 = 40 Pa to V2 = 4.0 m and p2 = 10 Pa along path B in Pi the p-V diagram in Fig. 18-58. It is then compressed back to V along either path A or path C. Compute the net work done by the gas for the complete cycle along (a) path BA and (b) path BC. V,

An ideal monatomic gas expands adiabatically from 0.530 m³ to 1.72 m³. If the initial pressure and temperature are 1.30 × 105 Pa and 355 K, respectively, find the number of moles in the gas, the final gas pressure, the final gas temperature, and the work done on the gas. HINT (a) the number of moles in the gas (Enter your answer to at least three significant figures.) mol (b) the final gas pressure (Enter your answer in Pa, to at least three significant figures.) Pa (c) the final gas temperature (in K) K (d) the work done on the gas (in J) J

tab Consider the following figure. (The x axis is marked in increments of 2.5 m³.) P (Pa). esc caps lock 6 x 106 4 X 106 2 x 106 V (m³) 1 (a) Determine the work done on a gas that expands from i to f as indicated in the figure. MJ (b) How much work is performed on the gas if it is compressed from f to / along the same path? MJ ! 1 F1 A NO 2 N FF 200 F2 W S # 3 80 F3 X E * D $ 4 F4 R C % 5 F MacBook Air T V の‥ 6 F6 G & 7 F7 H B 2 E

20-2 An ideal gas undergoes the thermodynamic process shown in the PV 2P. diagram in the figure. Determine whether each of the values (a) AU, (b)W, (c)Q for the gas is positive, negative, or zero. (Note that Wis the work done on the gas.) Hint: First use the ideal gas law to find the initial and final temperatures in terms of Po and Vo and determine if the final temperature is greater than, less than, or equal to the initial temperature. AU? W? Q? V₂₂ 2V₂

a) Consider a process involving an ideal diatomic gas with n = 3mol, following p = aV, where a = 1 x 105 Pa/m³ is a constant. The gas ex- pands from volume V; = 1 m³ to V; = 4m3. P2 Find the (i) work done on the gas. (ii) heat entering the gas. 1 (iii) change in the internal energy of the gas. b) Now consider the cycle depicted in the figure, involving the same amount of gas as in the previous part. A → B is the process described in the previous subtask, B → C an isochor and C → A an isobar. Additionally, V2/V1 = n = 4 and Vi = 1 m³. Find the Pi 3 i) work done by the gas during one loop of the cycle. V1 V2 V ii) thermal efficiency of the cycle. iii) maximum theoretical efficiency of a Car- not cycle having the same temperature extrema as in this cycle. iv) coefficient of performance of the cycle, if it were used as a refrigerator .

An ideal monatomic gas expands isothermally from 0.570 m³ to 1.25 m³ at a constant temperature of 800 K. If the initial pressure is 1.18 x 105 Pa find the following. (a) the work done on the gas (b) the thermal energy transfer Q J (c) the change in the internal energy J