Question

9) An insulated container contains V liters of hot water at temperature T. If M kg of ice at 0 °C is added to the water, what is the temperature of the system when it reaches equilibrium? Reminder, for water: 1L = 1 kg Cwater = 4190 Cice = 2100 ROK Lboll = 2.26 x 106 steam kg = 2000 .,Lmelt = 3.33 x 105 kg kg kg 10) In an engine, after the fuel is ignited, there is a fast, adiabatic expansion of the gas in the cylinder. If n moles of air (gas) starts this process at T, and expands from Vito V, what is the work done by the air (gas) on the piston during this expansion? Assume air is a diatomic ideal gas. 11) In an electric power plant (a heat engine) energy as heat is input at a temperature of T, and exhaust heat is output at a temperature of Tc. This heat engine has an efficiency that is 55% (0.55 times) that of an ideal engine operating between these same temperatures. If the maximum waste heat that can be output at Te is Qout Joules per second (Watrs), what is the maximum Work (electrical output) that can be provided by the power plant? 12) A container of Helium, a monatomic ideal gas, starts at P and V. The pressure of the gas is first increased at a constant volume to a pressure P, and then the volume of the gas is increased at the pressure P, until it reaches V, What is the total heat input into the gas during this two-step process?

Answer 1

botwater heat taken by ice 9 This queotion in baped on boricible of calorimetry beat given by the Jet final equila temperature=y milyt miso (T-0) z masw (Ti-TJ) Mw = 6.65L=6.8kg., ht=lmelt Ti=85°C, Mi= 1.65kg. 3.33x165 168X2160 + 1.658 4190 CTH) = 6.6*41907(85-TE) 365+ Tt C1.65*4190 +6.5x4190) = 6.574190x85 7+(4190*(1-65+6-5)) - 1-65X 3-33x105 1768825 y=51.7°¢ Anx -T2 Vans 218 TJ V 2/5 option to correct 10 Now riadialbetic TTVN for diatonic gax=715 Tevi TH= Ti (**)485 7108345 Now Woskedene miadiabatic proceo !- ner CTA-To) -0-032X5B *CTE ME PUS_T) 20-032xX834XTO crdi- Se (ORY onla = 233J option L P Correct

12 310 635 efficiency (8) = 4 = 1-TC -Te TH coreal efficiency = 1- Te zi- TH 50-5110 given Engine hap chilency 551 otthis. Now efficiency Qin-Qout = 0.28 zosson Qua Qin-Qout 20-20 fout - 0.72; Cmia daut 8.5x105 0:72 072 Float) Work done = Qin Quut = 0.5*105 = 3 33x105 IN By Appobaric proceso Theat supplied 9 - McRot = nur (TI-TC) ni hai (MRTK-TOxNx) = OxV4-Pinzg - CPA VA-POVE) - Ho (34**•S-1642-5) = 33875x1057 At i socheric powerpoQ-n crot 69= 3 MR (Tt-To) = Z (4CPt-Po) )x109 m3 28.62.8x1023. (volureni) Now Isobaric proceso y 082= nCPOT={net-To) 25 CPANA-P7V= x24(441 z 1987 z 1950

Total beat supplied a oQ1+O2 =1950 +8625 = 2013J And correet Си