Reservoir A has a temperature of 20 degrees C, and reservoir B has a temperature of 45 degrees C. A heat engine is built to receive heat from reservoir and output heat to the other reservoir. Which reservoir could provide the heat input.

Reservoir A has a temperature of 20 degrees C, and reservoir B has a temperature of 45 degrees C. A heat engine is built to receive heat from reservoir and output heat to the other reservoir. Which reservoir could provide the heat input.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter22: Entropy And The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 34PQ

See similar textbooks

Similar questions

If a gas is compressed isothermally, which of the following statements is true? (a) Energy is transferred into the gas by heat. (b) No work is done on the gas. (c) The temperature of the gas increases. (d) The internal energy of the gas remains constant. (e) None of those statements is true.
A coal power plant consumes 100,000 kg of coal per hour and produces 500 MW of power. If the heat of combustion of coal is 30 MJ/kg, what is the efficiency of the power plant?
A heat pump used for heating shown in Figure P18.25 is essentially an air conditioner installed backward. It extracts energy from colder air outside and deposits it in a warmer room. Suppose the ratio of the actual energy entering the room to the work done by the devices motor is 10.0% of the theoretical maximum ratio. Determine the energy entering the room per joule of work done by the motor given that the inside temperature is 20.0C and the outside temperature is 5.00C. Figure P18.25
Use a PV diagram such as the one in Figure 22.2 (page 653) to figure out how you could modify an engine to increase the work done.
You are working on a summer job at a company that designs non-traditional energy systems. The company is working on a proposed electric power plant that would make use of the temperature gradient in the ocean. The system includes a heat engine that would operate between 20.0C (surface-water temperature) and 5.00C (water temperature at a depth of about 1 km). (a) Your supervisor asks you to determine the maximum efficiency of such a system. (b) In addition, if the electric power output of the plant is 75.0 MW and it operates at the maximum theoretically possible efficiency, you must determine the rate at which energy is taken in from the warm reservoir. (c) From this information, if an electric bill for a typical home shows a use of 950 kWh per month, your supervisor wants to know how many homes can be provided with power from this energy system operating at its maximum efficiency. (d) As energy is drawn from the warm surface water to operate the engine, it is replaced by energy absorbed from sunlight on the surface. If the average intensity absorbed from sunlight is 650 W/m2 for 12 daylight hours on a clear day, you need to find the area of the ocean surface that is necessary for sunlight to replace the energy absorbed into the engine. (e) From this information, you need to determine if there is enough ocean surface on the Earth to use such engines to supply the electrical needs for all the homes associated with the Earths population. Assume the energy use for a home in part (c) is an average over the entire planet. (f) In view of your results in this problem, your supervisor has asked for your conclusion as to whether such a system is worthwhile to pursue. Note that the fuel (sunlight) is free.
A heat engine operates between two reservoirs at 800 and 20°C. One-half of the work output of the heat engine is used to drive a Carnot heat pump that removes heat from the cold surroundings at 2°C and transfers it to a house maintained at 22°C. If the house is losing heat at a rate of 62,000 kJ/h, determine the minimum rate of heat supply to the heat engine required to keep the house at 22°C.
The motor that drives a refrigerator produces 151 W of useful power. The hot and cold temperatures of the heat reservoirs are 20.0°C and -5.00°C. What is the maximum possible amount of ice it can produce in 2.00 h from water that is initially at 8.00°C? Latent heat of fusion of ice is 333700 J/kg and specific heat capacity of water is 4186 J/(kg-K). kg
A heat pump (h=0.3) uses 2500J of work to transfer heat energy. a)how much heat energy is absorbed by the hot reservoir? b) how much heat energy is released by the cold reservoir?
A 0.0800 kg sample of a gas is heated from 25 °C to 225 °C. During this process, 340 J of work is done by the gas and its internal energy increases by 9430 J. How much heat is transferred to the gas? Q = J What is the specific heat of the gas for this process? J/(kg · K) c =
A calorimeter is used to measure the energy released when a new exotic rocket fuel and oxidizer are burned. The calorimeter is a closed tank with the fuel and oxidizer, and this tank is located inside a larger tank of water.When the rocket propellant burns, heat from the closed inner tank is transferred to the water, and the rise in temperature of the water is used to determine the amount of energy released. A stirrer is used to stir the water; it does work per second (power) of 4.0 kW. In a one minute period the heat transfer from the inner tank to the water is 2000 kJ and the heat transfer from the water to the surroundings is 30 kJ.a) Determine the increase in the internal energy of the water in Joules.b) What is the final temperature of the water, in degrees C if the tank contains 0.1 m3 of water and was at 300 K initially ? The density of water is 1000 kg/m3 and the heat capacity of water is 1 calorie/gram-Kelvin. One calorie is 4.1855 Joules.
A sample of ideal gas is in a cylinder with a movable piston. 600 J of heat is added to the gas in an isothermal process. As the gas expands, pushing against the piston, how much work does it do?
A 600-MW steam power plant, which is cooled by a nearby river, has a thermal efficiency of 40 percent. Determine the rate of heat transfer to the river water. Will the actual heat transfer rate be higher or lower than this value? Why?