Carnot engine Definition and 107 Threads

Homework Statement A Carnot engine is operated as a refrigerator, taking in 18 J of heat every second and expelling 20 J into a 23oC room. What is the temperature inside the refrigerator? a. 15.4oC b. 3.33oC c. -6.62 oC d. -15.4 oC Homework Equations e=1-T(cold)/T(hot) U=Q-W...

Homework Statement 8. A house is cooled by an air conditioner. The outside temperature is 32°C and the inside temperature is 21°C. The heat leakage into the house is 9000 kcal/hr. If the air conditioner has the efficiency of a Carnot engine, what is the mechanical power required to keep the...

Homework Statement I have to draw a temperature versus entropy for a carnot engine. My solutions say that as a parallel to the PV diagram, the adiabatics on the TS diagram are vertical, going from t2 to t1 and vise versa. My question is really how an adiabatic change results in a temperature...

Homework Statement You want to boil a pot of water at 20C by heating it to 100C. I suggest a way of heating the pot in a reversible manner: simply inserting a Carnot engine between the reservoir (at 100C) and the pot. The Carnot engine operates between two temperatures, absorbing heat dQ_1...

Homework Statement A possible ideal gas cycle operates as follows: (i) From an initial state (p_1,V_1), the gas is cooled at constant pressure to (p_1,V_2); (ii) the gas is heated at constant volume to (p_2,V_2); (iii) the gas expands adiabatically back to (p_1,V_1). Assuming...

Homework Statement What is the relationship between the heat absorbed and rejected by the reservoirs and their temperature. If a heat pump is used to transfer heat what is the rate at which heat is added to the hot reservoir in terms of the temperatures of the reservoir and the work done by...

Homework Statement (a.) For an Ideal Gas Carnot engine, what is the relationship between heat absorbed and rejected by the reservoirs and their temperature? If a heat pump is used to transfer this heat, what is the rate at which heat is added to the hot reservoir in terms of the temperatures of...

Homework Statement 1. A heat engine operating between 200°C and 80.0°C achieves 20.0% of the maximum possible efficiency. What energy input will enable the engine to perform 10.0 kJ of work? Homework Equations e =1- Tc/Th W=e*Qh The Attempt at a Solution I got the answer but I...

Homework Statement A 200 litre container of boiling water and a 200 litre container of ice cold water are used as heat source and sink for a Carnot engine. Calculate the maximum amount of useful work that can be obtained from the system and the final temperature of the two containers of...

Homework Statement Determine which gives the higher efficiency of a Carnot engine, increasing the temperature of the hot reservoir, or decreasing the temperature of the cold reservoir by the same amount. Justify your answer carefully. Homework Equations (TH-TC)/TH)The Attempt at a Solution By...

Homework Statement A house is heated by means of a carnot engine operating in reverse (Heat Pump). The outside Temperature (Tc) is 270k, and the required inside temperature (Th) is 300k. If heating the house to this temperature normally requires 10kW of electrical heating, how much power is...

Homework Statement An ideal monatomic gas is the working substance of a Carnot engine. During the isothermal expansion, the volume doubles. The ratio of the final volume to the initial volume in the adiabatic expansion is 5.7. The work output of the engine is 9x10^{5}J in each cycle. Compute...

I think it is due to friction and the carnot efficiency is derived in a reversible cycle. Also,can i build just a little bit irreversible but still carnot? But if irreversible how can i draw the graph? Still smooth line?

Homework Statement A Carnot heat engine operates between temperatures Th and Tc. (a) If Th = 515 K and Tc = 363 K, what is the efficiency of the engine? 0.30 Your answer is correct. (b) What is the change in its efficiency for each degree of increase in Th above 515 K? ? K-1 (c) What...

Hello, For a reversible heat engine between temperatures T_1 and T_2, the ratio of heat going in and out the engine is \frac{Q_1}{Q_2} = \frac{T_1}{T_2} (second law). Say T_1 = 200 K and T_2 = 273 K, then heat goes from 2 to 1 and as we can see, the ratio of heat that goes in the engine is...

Homework Statement A Carnot engine performs work at the rate of 360 kW while using 720 kcal of heat per second.If the temperature of the heat source is 650 C, at what temperature is the waste heat exhausted? Homework Equations because Th,Qh,and W are given so i going to use this formula...

Homework Statement A Carnot engine runs between a high temperature of 500 C and a low temperature of 50 C. The isothermal expansion (upper branch) occurs between a volume of 0.5L and 1.0L. The isothermal contraction (lower branch) occurs between 2.0L and 1.0L. There are 2 moles of gas...

A Carnot air conditioner takes energy from the thermal energy of a room at 76°F and transfers it as heat to the outdoors, which is at 96°F. For each joule of electric energy required to operate the air conditioner, how many joules are removed from the room? Attempt at problem 76 + 273 = 349 96...

Homework Statement Two heat engines operating on Carnot cycles are arranged in series. The first engine A receives heat at 927 deg C and rejects heat to a reservoir at a temperature T. The second engine B receives the heat rejected by the first engine, and in turn rejects heat to a reservoir...

Homework Statement The exhaust temperature of a Carnot heat engine is 401◦ C. What is the intake temperature if the efficiency of the engine is 40.2 %? Answer in units of ◦ C. Homework Equations e = 1 - Tc/Th (all in Kelvin) The Attempt at a Solution 0.402 = 1 - Tc/ (401+273) = 1...

Homework Statement A Carnot engine working with a monatomic gas operating between two temps, 288K and 497K. The engine performs 800 J of net work. Homework Equations Q = nRT ln (V final/V initial) The Attempt at a Solution I don't have enough info for the above equation. I...

Homework Statement A Carnot engine has 40 g of helium gas as its working substance. It operates between two reservoirs of temperatures T1 = 400°C and T2 = 60°C. The initial volume of the gas is V1 = 2.0 X 10-2 m3, the volume after isothermal expansion is V2 = 4.0 X 10-2 m3, and the volume...

Homework Statement I'm trying to find the final temperature of a carnot engine with two finite thermal reservoirs. We're told that the heat capacities for both reservoirs are constant (and equal) and to regard the change in each reservoir's temperature during any 1 cycle as negligible...

Homework Statement An ideal Carnot engine operates between a heat reservoir and a block of ice of mass M. An external energy source maintains the reservoir at a constant temperature T_{h}. At time t=0 the ice is at its melting point T_{0}, but it is insulated from everything except the...

Note this is more of a coursework question about the theory behind Carnot engines as opposed to an actual homework question. Homework Statement The Attempt at a Solution So I am reading the theory behind a Carnot Engine and I am a little confused about the cooling stages of the Carnot cycle...

Homework Statement A steam engine has a cylinder 80cm in diameter with a piston that has a total travel length of 1.8m. Assume that there is no "dead space" between the cylinder head and the piston when the piston is farthest in the cylinder. Steam is piped into the cylinder head from an...

Homework Statement This is from "Equilibrium Statistical Physics" by Plischke and Bergerson, problem 1.1: "Consider a Carnot engine working between reservoirs at temperatures T1 and T2. The working substance is an ideal gas obeying the equation of state [ PV=Nk_BT ], which may be taken to be...

Homework Statement A Carnot Engine operating between 900 Fahrenheit and 90 Fahrenheit produces 40,000 ft-lb of work. Determine (a) the heat supplied, (b) the change in entropy during heat rejection and (c) the thermal efficiency of engine. (answers should be in BTU) Homework Equations What...

quick question, is the difference between a carnot engine to an engine is that the engines eff is less than or equal 1-(cold temp / hot temp), and the carnot is the max of this which is just equal 1-(cold temp / hot temp)?

Homework Statement An ideal Carnot engine produces a power output of 5kW at a thermal efficiency of 35% while rejecting heat reversibly to a reservoir at 30degrees. It achieves this output while executing 10 cycles per second. a) What temperature is the engine receiving its heat supply...

A Carnot heat engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. In 5 minutes of operation of the engine, the heat rejected by the engine melts a mass of ice equal to 2.85×10−2 Kg. Throughout this...

Homework Statement A Carnot engine using a gas operates between 2 reservoirs of temperatures 1000K and 280K. The work output per cycle is 1kJ. a) What is the efficiency? b) What is the entropy change of the gas per cycle due to the heat transfer at the hot reservoir? Homework Equations...

A carnot engine uses 0.05kg of air as the working substance. The temperature limits of the cycle are 300K and 940K, the maximum pressure is 8400KPa, and the heat added per cycle is 4.2KJ. Determine the pressure and volume at each state of the cycle. r(gamma)=1.4 and R=0.287KJ/Kg Kim pretty sure...

Homework Statement An ice making plant consists of a reversed Carnot engine extracting heat from a well- insulated box. The temperature in the icebox is -5C and the temperature of ambient air is 30C. Water of an initial temp 30C is placed in the icebox and allowed to freeze and cool to -5C...

Homework Statement From the hot reservoir at a temperature of T1, Carnot Engine A takes an input heat of 5550J, delivers 1750J of work and rejects heat to a cold reservoir that has a temperature of 503K. This cold reservoir also serves as the hot reservoir for a second Carnot Engine, B, which...

Homework Statement An ideal (Carnot) engine has an efficiency of 50 % If it were possible to run it backward as a heat pump, what would be its coefficient of performance? Homework Equations COP = (TL) / (TH - TL ) The Attempt at a Solution no temperatures are given. I just...

Homework Statement A heat engine operates in a Carnot cycle between 80 degrees C and 350 degrees C. It absorbs 21,000 J of energy per cycle from the hot reservoir. a. THe duration of each cycle is 1s. What is the mechanical power output of the engine? b. How much energy does it expel in each...

Homework Statement The exhaust temperature of a Carnot heat engine is 121◦C. What is the intake temperature if the efficiency of the engine is 13.4 %? Answer in units of ◦C. Homework Equations e=1-(Tc/Th) The Attempt at a Solution This seems like just a plug and chug problem...

Homework Statement Consider 2 identical bodies of constant heat capacity Cp and with negligble termal expansion coefficients. Initial temperatures are T1 and T2. a) When they are placed in thermal contact in an adiabatic enclosure, what is their final temperature? b) The 2 bodies are...

A firebox is at 750K, and the ambient temperature is 300K. The efficiency of a Carnot engine doing 150J of work as it transports energy between these constant-temperature baths is 60.0%. The Carnot engine must take in energy 150J/.600 = 250J from the hot reservoir and must put out 100J of...

Homework Statement An ideal Carnot engine takes in 160 kcal of heat at 110°C and exhausts some of this at 10°C. How much work (in joules) must have been done by the engine? Homework Equations The engine's efficiency is ε = (TH - TL)/TH. The hint tells me that I need to use the First Law of...

A Carnot heat engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. In 5 minutes of operation of the engine, the heat rejected by the engine melts a mass of ice equal to 3.40×10^−2 kg. Throughout this problem...

Homework Statement Which of the following statements about a Carnot engine is true? a) Any Carnot engine has an efficiency of 100% b) Irreversible energies have the greatest possible efficiency. c) Heat can spontaneously flow from a cold reservoir to a hotter reservoir. d) If a process is...

Homework Statement A heat pump is used to heat a building. The outside temp is -5.0 Celsius and the temp inside the building is to be maintained at 22 Celsius. The pump's coefficient of performance is 3.8, and the heat pump delivers 7.54MJ as heat to the building each hour. If the heat pump...

[SOLVED] Carnot engine - please help asp I just typed a whole question and as I typed it I solved it, lol! Homework Statement In the 1st stage of a 2-stage Carnot engine, energy is absorbed as heat Q1 at temp T1, work W1 is done, and energy is expelled as heat Q2 at lower temp T2. The...

Homework Statement A Carnot heat engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. In 5 minutes of operation of the engine, the heat rejected by the engine melts a mass of ice equal to 3.50×10−2 kg ...

Homework Statement A Carnot heat engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. In 5 minutes of operation of the engine, the heat rejected by the engine melts a mass of ice equal to 3.30×10^-2 kg...

1. Homework Statement 1) A 200 litre container of boiling water and a 200 litre of ice cold water are used as heat source and sink for a carnot engine. Calculate the maximum amount of useful work that can be obtained from the system and the final temperature of the two containers of water...

i have this example problem...and i want to know how to answer this problem :confused: a carnot engine is operated with its maximum temperature equal to 700K and 300kW were rejected. what is the sink temperature, if 450kW enters at the upper temperature. tanx for your help..

hi i just want to know the formula of the otto cycle for the folowwing parameter: compression ratio,cycle work,heat added,heat rejection,thermal efficiency and mean effective pressure. and also may i know the formula for getting the pressure (bar) and the volume(m3/kg) temperature(K) for...