Physics for Scientists and Engineers with Modern Physics
Physics for Scientists and Engineers with Modern Physics
4th Edition
ISBN: 9780131495081
Author: Douglas C. Giancoli
Publisher: Addison-Wesley
bartleby

Videos

Textbook Question
Book Icon
Chapter 20, Problem 30P

(II) A central heat pump updating as an air conditioner draws 33,000 Btu per hour from a building and operates between the temperatures of 24°C and 38°C. (a) If its coefficient of performance is 0.20 that of a Carnot air conditioner, what is the effective coefficient of performance? (b) What is the power (kW) required of the compressor motor? (c) What is the power in terms of hp?

Blurred answer
Students have asked these similar questions
(II) Energy may be stored by pumping water to a high reservoir when demand is low and then releasing it to drive turbines during peak demand. Suppose water is pumped to a lake 115 m above the turbines at a rate of 1.00 × 10° kg/s for 10.0 h at night. (a) How much energy (kWh) is needed to do this each night? (b) If all this energy is released during a 14-h day, at 75% efficiency, what is the average power output? (ID Water is stored in an artificial lake created by a lam
(ii) Electrical Energy (in kWh) consumed by two Electric Freezers of rating 1500 W for 24 h of each day= (iii) Electrical Energy(in kWh) consumed by ten Tube lights of rating 20 W for 12 h of each day = (iv) Total energy(in kWh) consumed in the month November'2020 = (v) Electricity bill(in riyals) for the month of November'2020 =
b) Energy may be stored for use during peak demand by pumping water to a high reservoir when needed. Suppose water is pumped to a lake 135 m above the turbines and at a rate of 1.35 x 10 kgs" for 10 hrs at night. ) How much energy (kWh) is needed to do this each night. i) If all this energy is released during a-14 h day, at 75% efficiency, what is the average power output? e) State three forms of environmental polution and how they can be prevented.

Chapter 20 Solutions

Physics for Scientists and Engineers with Modern Physics

Ch. 20 - Discuss the factors that keep real engines from...Ch. 20 - Prob. 8QCh. 20 - Describe a process in nature that is nearly...Ch. 20 - (a) Describe how heat could be added to a system...Ch. 20 - Suppose a gas expands to twice its original volume...Ch. 20 - Give three examples, other than those mentioned in...Ch. 20 - Which do you think has the greater entropy, 1 kg...Ch. 20 - (a) What happens if you remove the lid of a bottle...Ch. 20 - Prob. 15QCh. 20 - Prob. 16QCh. 20 - Prob. 17QCh. 20 - The first law of thermodynamics is sometimes...Ch. 20 - Powdered milk is very slowly (quasistatically)...Ch. 20 - Two identical systems are taken from state a to...Ch. 20 - It can he said that the total change in entropy...Ch. 20 - Use arguments, other than the principle of entropy...Ch. 20 - (I) A heat engine exhausts 7800 J of heat while...Ch. 20 - (I) A certain power plant puts out 580 MW of...Ch. 20 - (II) A typical compact car experiences a total...Ch. 20 - (II) A four-cylinder gasoline engine has an...Ch. 20 - (II) The burning of gasoline in a car releases...Ch. 20 - (II) Figure 2017 is a PV diagram for a reversible...Ch. 20 - (III) The operation of a diesel engine can be...Ch. 20 - (I) What is the maximum efficiency of a heat...Ch. 20 - (I) It is not necessary that a heat engines hot...Ch. 20 - (II) A heal engine exhausts its heat at 340C and...Ch. 20 - (II) (a) Show that the work done by a Carnot...Ch. 20 - (II) A Carnot engines operating temperatures are...Ch. 20 - (II) A nuclear power plant operates at 65% of its...Ch. 20 - (II) A Carnot engine performs work at the rate of...Ch. 20 - (II) Assume that a 65 kg hiker needs 4.0 103 kcal...Ch. 20 - (II) A particular car does work at the rate of...Ch. 20 - (II) A heat engine utilizes a heat source at 580C...Ch. 20 - (II) The working substance of a certain Carnot...Ch. 20 - (III) A Carnot cycle, shown in Fig. 20-7, has the...Ch. 20 - (III) One mole of monatomic gas undergoes a Carnot...Ch. 20 - (III) In an engine that approximates the Otto...Ch. 20 - (I) If an ideal refrigerator keeps its contents at...Ch. 20 - (I) The low temperature of a freezer cooling coil...Ch. 20 - (II) An ideal (Carnot) engine has an efficiency of...Ch. 20 - (II) An ideal heal pump is used to maintain the...Ch. 20 - (II) A restaurant refrigerator has a coefficient...Ch. 20 - (II) A heat pump is used to keep a house warm at...Ch. 20 - (II) (a) Given that the coefficient of performance...Ch. 20 - (II) A Carnot refrigerator (reverse of a Carnot...Ch. 20 - (II) A central heat pump updating as an air...Ch. 20 - (II) What volume of water at 0C can a freezer make...Ch. 20 - (I) What is the change in entropy of 250g of steam...Ch. 20 - (I) A 7.5-kg box having an initial speed of 4.0m/s...Ch. 20 - (I) What is the change in entropy of 1.00 m3 of...Ch. 20 - (II) If 1.00m3 of water at 0C is frozen and cooled...Ch. 20 - (II) If 0.45kg f water at 100C is changed by a...Ch. 20 - (II) An aluminum rod conducts 9.50 cal/s from a...Ch. 20 - (II) A 2.8-kg piece of aluminum at 43.0C is placed...Ch. 20 - (II) An ideal gas expands isothermally (T = 410 K)...Ch. 20 - (II) When 2.0 kg of water at 12.0C is mixed with...Ch. 20 - (II) (a) An ice cube of mass m at 0C is placed in...Ch. 20 - (II) The temperature of 2.0mol of an ideal...Ch. 20 - (II) Calculate the change in entropy of 1.00kg of...Ch. 20 - (II) An ideal gas of n moles undergoes the...Ch. 20 - (II) Two samples of an ideal gas are initially at...Ch. 20 - (II) A 150-g insulated aluminum cup at 15C is...Ch. 20 - (II) (a) Why would you expect the total entropy...Ch. 20 - (II) 1.00 mole of nitrogen (N2) gas and 1.00 mole...Ch. 20 - (II) Thermodynamic processes are sometimes...Ch. 20 - (III) The specific heat per mole of potassium at...Ch. 20 - (III) Consider an ideal gas of n moles with molar...Ch. 20 - (III) A general theorem states that the amount of...Ch. 20 - (III) Determine the work available in a 3.5-kg...Ch. 20 - (I) Use Eq. 2014 to determine the entropy of each...Ch. 20 - (II) Suppose that you repeatedly shake six coins...Ch. 20 - (II) Calculate the relative probabilities, when...Ch. 20 - (II) (a) Suppose you have four coins, all with...Ch. 20 - Prob. 58PCh. 20 - (II) Energy may be stored for use during peak...Ch. 20 - (II) Solar cells (Fig. 20-22) can produce about...Ch. 20 - Prob. 61PCh. 20 - It has been suggested that a heat engine could be...Ch. 20 - A heat engine takes a diatomic gas around the...Ch. 20 - A 126.5-g insulated aluminum cup at 18.00C is...Ch. 20 - (a) At a steam power plant, steam engines work in...Ch. 20 - (II) Refrigeration units can be rated in tons. A...Ch. 20 - Prob. 67GPCh. 20 - (a) What is the coefficient of performance of an...Ch. 20 - The operation of a certain heat engine takes an...Ch. 20 - A car engine whose output power is 155 hp operates...Ch. 20 - Suppose a power plant delivers energy at 850 MW...Ch. 20 - 1.00 mole of an ideal monatomic gas at STP first...Ch. 20 - Two 1100-kg cars are traveling 75 km/h in opposite...Ch. 20 - Metabolizing 1.0 kg of fat results in about 3.7 ...Ch. 20 - A cooling unit for a new freezer has an inner...Ch. 20 - Prob. 76GPCh. 20 - The Stirling cycle shown in Fig 20-27, is useful...Ch. 20 - A gas turbine operates under the Brayton cycle,...Ch. 20 - Thermodynamic processes can be represented not...Ch. 20 - An aluminum can, with negligible heat capacity, is...Ch. 20 - Prob. 81GPCh. 20 - A bowl contains a large number of red, orange, and...
Knowledge Booster
Background pattern image
Physics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Physics for Scientists and Engineers, Technology ...
Physics
ISBN:9781305116399
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Text book image
University Physics Volume 1
Physics
ISBN:9781938168277
Author:William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:OpenStax - Rice University
Text book image
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College
Text book image
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Text book image
Glencoe Physics: Principles and Problems, Student...
Physics
ISBN:9780078807213
Author:Paul W. Zitzewitz
Publisher:Glencoe/McGraw-Hill
The Second Law of Thermodynamics: Heat Flow, Entropy, and Microstates; Author: Professor Dave Explains;https://www.youtube.com/watch?v=MrwW4w2nAMc;License: Standard YouTube License, CC-BY