A Carnot engine runs between a hot reservoir at T, and a cold reservoir at T. If one of the temperatures is either increased or decreased by 3.5 K, which of the following changes would increase the efficiency by the greatest amount? / A. increasing Th B. increasing T C. decreasing Th D. decreasing T

A Carnot engine runs between a hot reservoir at T, and a cold reservoir at T. If one of the temperatures is either increased or decreased by 3.5 K, which of the following changes would increase the efficiency by the greatest amount? / A. increasing Th B. increasing T C. decreasing Th D. decreasing T

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter15: Thermodynamics

Section: Chapter Questions

Problem 28PE: A certain gasoline engine has an efficiency of 30.0%. What would the hot reservoir temperature be...

See similar textbooks

Similar questions

This problem compares the energy output and heat transfer to the environment by two different types of nuclear power stationsone with the normal efficiency of 34.0%, and another with an improved efficiency of 40.0%. Suppose both have the same heat transfer into the engine in one day. 2.501014J. (a) How much more electrical energy is produced by the more efficient power station? (b) How much less heat transfer occurs to the environment by the more efficient power station? (One type of more ef?cient nuclear power station, the gas—cooled reactor, has not been reliable enough to be economically feasible in spite of its greater eficiency.)
A gun is a heat engine. In particular, it is an internal combustion piston engine that does not operate in a cycle, but comes apart during its adiabatic expansion process. A certain gun consists of 1.80 kg of iron. It fires one 2.40-g bullet at 320 m/s with an energy efficiency of 1.10%. Assume the body of the gun absorbs all the energy exhaustthe other 98.9%and increases uniformly in temperature for a short time interval before it loses any energy by heat into the environment. Find its temperature increase.
A sample of a monatomic ideal gas is contained in a cylinder with a piston. Its stale is represented by the dot in the PV diagram shown in Figure OQ22.9. Arrows A through E represent isobaric, isothermal, adiabatic, and isovolumetric processes that the sample can undergo. In each process except D, the volume changes by a factor of 2. All five processes are reversible. Rank the processes according to the change in entropy of the gas from the largest positive value to the largest-magnitude negative value. In your rankings, display any cases of equality.
A heliumfilled toy balloon has a gauge pressure of 0.200 atm and a volume of 10.0 L. How much greater is the internal energy of the helium in the balloon than it would be at zero gauge pressure?
Explain how water’s entropy can decrease when it freezes without violating the second law of thermodynamics. Specifically, explain what happens to the entropy of its surroundings.
A certain gasoline engine has an efficiency of 30.0%. What would the hot reservoir temperature be for a Carnot engine having that eficiency, if it operates with a cold reservoir temperature of 200°C?
An ideal gas is taken through a Carnot cycle. The isothermal expansion occurs at 250C, and the isothermal compression takes place at 50.0C. The gas takes in 1.20 103 J of energy from the hot reservoir during the isothermal expansion. Find (a) the energy expelled to the cold reservoir in each cycle and (b) the net work done by the gas in each cycle.
Argon enters a turbine at a rate of 80.0 kg/min, a temperature of 800C, and a pressure of 1.50 MPa. It expands adiabatic ally as it pushes on the turbine blades and exits at pressure 300 kPa. (a) Calculate its temperature at exit. (b) Calculate the (maximum) power output of the turning turbine, (c) The turbine is one component of a model closed-cycle gas turbine engine. Calculate the maximum efficiency of the engine.
1. A Carnot engine works at high temperature 600 Kelvin with the efficiency of 40%. If the efficiency of the engine is 75% and the low temperature kept constant, what is the high temperature? answer: High Temp = 1440k
1. A Carnot engine operates between reservoirs at 625 and 315 K. If the engine absorbs 115J per cycle at the hot reservoir. Calculate (a) The efficiency, e, of the engine e= (b) The work output per cycle W. per cycle
6. A Carnot engine operates between reservoirs at temperatures T. and Ty and performs an amount of work W per cycle. Expressed in terms of these variables, what are the amounts of heat input and exhaust-heat output per cycle?
2. An Carnot engine absorbs heat at high temperature 800 Kelvin and efficiency of the Carnot engine is 50%. What is the high temperature to increase efficiency to 80% if the low temperature kept constant. answer: High Teamp = 2000k