College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 7, Problem 23CQ
Shivering is an involuntary response to lowered body temperature. What is the efficiency of the body when shivering, and is this a desirable value?
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
A 500 N object is lifted to a height of 1 meter using a 10 m longinclined ramp. The laborer only has to use 50 N of force to pull thecart. What is the efficiency of the ramp?a.50%b.75%c.100%d.150%
What is the efficiency of an out-of-condition professor who does 1.90 ✕ 105 J of useful work while metabolizing 510 kcal of food energy? (Enter your answer as a percentage. Enter a number.)%
How many food calories (in kcal) would a well-conditioned athlete metabolize in doing the same work with an efficiency of 25%? (Enter a number.)kcal
Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity. Suppose a person shoveling a footpath metabolizes food at the rate of 750 W. (The efficiency of a person shoveling is 3%.)
(a)
What is her useful power output (in W)?
Answer________________ W
(b)
How long (in s) will it take her to lift 2600 kg of snow 1.20 m? (This could be the amount of heavy snow on 20 m of footpath.)
Answer________________ s
(c)
How much waste heat transfer in kilojoules will she generate in the process?
Answer________________ kJ
Chapter 7 Solutions
College Physics
Ch. 7 - Give an example of something think of as work in...Ch. 7 - Give an example of a situation in which there is a...Ch. 7 - Describe a situation in which a force is exerted...Ch. 7 - The person in Figure 7.33 does work on the lawn...Ch. 7 - Work done on a system puts energy into it Work...Ch. 7 - When solving for speed in Example 7.4, we kept...Ch. 7 - In Example 7.7, we calculated the final speed of a...Ch. 7 - Does the work you do on a book when you lift it...Ch. 7 - What is a conservative force?Ch. 7 - The force exerted by a diving board is...
Ch. 7 - Define mechanical energy. What is the relationship...Ch. 7 - What is the relationship of potential energy to...Ch. 7 - Consider the following scenario. A car for which...Ch. 7 - Describe the energy transfers and transformations...Ch. 7 - Do devices with efficiencies of less than one...Ch. 7 - List four different forms or types of energy. Give...Ch. 7 - List the energy conversions that occur when riding...Ch. 7 - Most electrical appliances are rated in watts....Ch. 7 - Explain, in terms of the definition of power, why...Ch. 7 - A spark of static electricity, such as that you...Ch. 7 - Explain why it is easier to climb a mountain on a...Ch. 7 - Do you do work on the outside world when you rub...Ch. 7 - Shivering is an involuntary response to lowered...Ch. 7 - Discuss the relative effectiveness of dieting and...Ch. 7 - What is the difference between energy conservation...Ch. 7 - If the efficiency of a coal-fired electrical...Ch. 7 - How much work does a supermarket checkout...Ch. 7 - A 75.0-kg person climbs stairs, gaining 2.50...Ch. 7 - (a) Calculate the work done on a 1500-kg elevator...Ch. 7 - Suppose a car travels 108 km at a speed of 30.0...Ch. 7 - Calculate the work done by an 85.0-kg man who...Ch. 7 - How much work is done by the boy pulling his...Ch. 7 - A shopper pushes a grocery cart 20.0 m at constant...Ch. 7 - Suppose the ski patrol lowers a rescue sled and...Ch. 7 - Compare the kinetic energy of a 20,000-kg truck...Ch. 7 - (a) How fast must a 3000-kg elephant move to have...Ch. 7 - Confirm the value given for the kinetic energy of...Ch. 7 - (a) Calculate the force needed to bring a 950-kg...Ch. 7 - A car's bumper is designed to withstand a 4.0-km/h...Ch. 7 - Boxing gloves are padded to lessen the force of a...Ch. 7 - Using energy considerations, calculate the average...Ch. 7 - A hydroelectric power facility (see Figure 7.38)...Ch. 7 - (a) How much gravitational potential energy...Ch. 7 - Suppose a 350-g kookaburra (a large kingfisher...Ch. 7 - In Example 7.7, we found that the speed of a...Ch. 7 - A 100-g toy car is propelled by a compressed...Ch. 7 - In a downhill ski race, surprisingly, little...Ch. 7 - A 5.00105 -kg subway train is brought to a stop...Ch. 7 - A pogo stick has a spring with a force constant of...Ch. 7 - A 60.0-kg skier with an initial speed of 12.0 m/s...Ch. 7 - (a) How high a hill can a car coast up (engine...Ch. 7 - Using values from Table 7.1, how many DNA...Ch. 7 - Using energy considerations and assuming...Ch. 7 - If the energy in fusion bombs were used to supply...Ch. 7 - (a) Use of hydrogen fusion to supply energy is a...Ch. 7 - The Crab Nebula (see Figure 7.41) pulsar is the...Ch. 7 - Suppose a star 1000 times brighter than our Sun...Ch. 7 - A person in good physical condition can put out...Ch. 7 - What is the cost of operating a 3.00-W electric...Ch. 7 - A large household air conditioner may consume 15.0...Ch. 7 - (a) What is the average power consumption in watts...Ch. 7 - (a) What is the average useful power output of a...Ch. 7 - A 500-kg dragster accelerates from rest to a final...Ch. 7 - (a) How long will it take an 850-kg car with a...Ch. 7 - (a) Find the useful power output of an elevator...Ch. 7 - (a) What is the available energy content, in...Ch. 7 - (a) How long would it takea 1.50105 -kg airplane...Ch. 7 - Calculate the power output needed for a 950-kg car...Ch. 7 - (a) Calculate the power per square meter reaching...Ch. 7 - (a) How long can you rapidly climb stairs...Ch. 7 - (a) What is the power output in watts and...Ch. 7 - Calculate the power output in watts and horsepower...Ch. 7 - (a) What is the efficiency of an out-of-condition...Ch. 7 - Energy that is not utilized for work or heat...Ch. 7 - Using data from Table 7.5, calculate the daily...Ch. 7 - What is the efficiency of a subject on a treadmill...Ch. 7 - Shoveling snow can be extremely taxing because the...Ch. 7 - Very large forces are produced in joints when a...Ch. 7 - Jogging on hard surfaces with insufficiently...Ch. 7 - (a) Calculate the energy in kJ used by a 55.0-kg...Ch. 7 - Kanellos Kanellopoulos flew 119 km from Crete to...Ch. 7 - The swimmer shown in Figure 7.44 exerts an average...Ch. 7 - Mountain climbers carry bottled oxygen when at...Ch. 7 - The awe-inspiring Great Pyramid of Cheops was...Ch. 7 - (a) How long can you play tennis on the 800 kJ...Ch. 7 - Integrated Concepts (a) Calculate the force the...Ch. 7 - Integrated Concepts A 75.0-kg cross-country skier...Ch. 7 - Integrated Concepts The 70.0-kg swimmer in Figure...Ch. 7 - Integrated Concepts A toy gun uses a spring with a...Ch. 7 - Integrated Concepts (a) What force must be...Ch. 7 - Unreasonable Results A car advertisement claims...Ch. 7 - Unreasonable Results Body fat is metabolized,...Ch. 7 - Construct Your Own Problem Consider a person...Ch. 7 - Construct Your Own Problem Consider humans...Ch. 7 - Integrated Concepts A 105-kg basketball player...
Additional Science Textbook Solutions
Find more solutions based on key concepts
41. A 0.300 kg oscillator has a speed of 95.4cm/s when its displacement is 3.00cm and 71.4 cm/s when its displ...
Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
The proton is a composite particle composed of three quarks, all of which are either up quarks (u; charge +23e)...
Essential University Physics: Volume 2 (3rd Edition)
16. On the Apollo 14 mission to the moon, astronaut Alan Shepard hit a golf ball with a 6 iron. The free-fall a...
Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
TEST YOUR UNDERSTANDING OF SECTION 1.5 The density of a material is equal to its mass divided by its volume. Wh...
University Physics with Modern Physics (14th Edition)
The electromagnetic spectrum of light is often arranged in terms of frequency. Which one of the following has t...
Lecture- Tutorials for Introductory Astronomy
The force, when you push against a wall with your fingers, they bend.
Conceptual Physics (12th Edition)
Knowledge Booster
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
- A typical automobile engine has an efficiency of 25 . Suppose that the engine of a 1000-kg automobile has a maximum power output of 140 hp. What is the maximum grade that the automobile can climb at 50 km/h if the frictional retarding force on it is 300 N?arrow_forwardWhat is the efficiency of a subject on a treadmill who puts out work at the rate of 100 W while consuming oxygen at the rate of 2.00 L/min? (Hint: See Table 7.5.)arrow_forwardWhat is the cost of operating a 3.00-W electric clock for a year if the cost of electricity is 0.0900 per kWh ?arrow_forward
- A man of mass 80 kg runs up a flight of stairs 20 m high in 10 s. (a) how much power is used to lift the man?(b) If the man’s body is 25 efficient, how much power does he expend?arrow_forward“ E=K+Uconstant is a special case of the work energy theorem.” Discuss this statement.arrow_forwardMost electrical appliances are rated in watts. Does this rating depend on how long the appliance is on? (When off, It is a zero-wan device.) Explain in terms of the definition of power.arrow_forward
- (a) What is the efficiency of an out-of-condition professor who does 2.10105J of useful work while metabolizing 500 kcal of food energy? (b) How many food calories would a well-conditioned athlete metabolize in doing the same work with an efficiency of 20%?arrow_forward(a) How fast must a 3000-kg elephant move to have the same kinetic energy as a 65.0-kg sprinter running at 10.0 m/s? (b) Discuss how the larger energies needed for the movement of larger animals would relate to metabolic rates.arrow_forwardFor the situation in Fig. 4.4a, if the applied force is removed, then the frictional force will continue to do work, so there is an energy transfer. Explain this transfer.arrow_forward
- A steam engines raises a 1800 kg mass vertically at the rate of 9 m/s. What is the power of the engine assuming an efficiency of 70%? The correct answer is 227 kW.arrow_forwardWhen a cyclist expends 1500 W of power to deliver mechanical energy to her bicycle at a rate of 100 W, find the efficiency of her body. Express your answer as a percentage.arrow_forwarda worker exerts a force of 119 N on a lever to raise a block. the efficiency of the lever is 91.6 percent. if the lever is moved 0.770 m, the block rises to a height of 0.180 m. what is the mass of the block ?arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- College PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax CollegeGlencoe Physics: Principles and Problems, Student...PhysicsISBN:9780078807213Author:Paul W. ZitzewitzPublisher:Glencoe/McGraw-HillUniversity Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice University
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningAn Introduction to Physical SciencePhysicsISBN:9781305079137Author:James Shipman, Jerry D. Wilson, Charles A. Higgins, Omar TorresPublisher:Cengage Learning
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College
Glencoe Physics: Principles and Problems, Student...
Physics
ISBN:9780078807213
Author:Paul W. Zitzewitz
Publisher:Glencoe/McGraw-Hill
University Physics Volume 1
Physics
ISBN:9781938168277
Author:William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:OpenStax - Rice University
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
An Introduction to Physical Science
Physics
ISBN:9781305079137
Author:James Shipman, Jerry D. Wilson, Charles A. Higgins, Omar Torres
Publisher:Cengage Learning
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