Physics for Scientists and Engineers with Modern Physics
10th Edition
ISBN: 9781337553292
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 19, Problem 38AP
(a)
To determine
The hourly rate at which water must evaporate from the skin of a person.
(b)
To determine
The fraction of water provided by fat
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
The rate at which a resting person converts food energy is called one’s basal metabolic rate (BMR). Assume that the resulting internal energy leaves a person’s body by radiation and convection of dry air. When you jog, most of the food energy you burn above your BMR becomes internalenergy that would raise your body temperature if it were not eliminated. Assume that evaporation of perspiration is the mechanism for eliminating this energy. Suppose a person is jogging for “maximum fat burning,” converting food energy at the rate 400 kcal/h above his BMR, and putting out energy by work at the rate 60.0 W. Assume that the heat of evaporation of water at body temperature is equal to its heat of vaporization at 100°C. (a) Determine the hourly rate at which water must evaporate from his skin. (b) When you metabolize fat, the hydrogen atoms in the fat molecule are transferred to oxygen to form water. Assume that metabolism of 1.00 g of fat generates 9.00 kcal of energy and produces 1.00 g of…
Overall, 80% of the energy used by the body must be eliminated as excess thermal energy and needs to be dissipated. The
mechanisms of elimination are radiation, evaporation of sweat (2,430 kJ/kg), evaporation from the lungs (38 kJ/h),
conduction, and convection.
A person working out in a gym has a metabolic rate of 2,500 kJ/h. His body temperature is 37°C, and the outside
temperature 22°C. Assume the skin has an area of 2.0 m2 and emissivity of 0.97. (o = 5.6696 × 10-8 w/m2 · K4)
(a) At what rate is his excess thermal energy dissipated by radiation? (Enter your answer to at least one decimal
place.)
1.8e2
W
(b) If he eliminates 0.44 kg of perspiration during that hour, at what rate is thermal energy dissipated by
evaporation of sweat? (Enter your answer to at least one decimal place.)
3.0e2
W
(c) At what rate is energy eliminated by evaporation from the lungs? (Enter your answer to at least one decimal
place.)
10.6
W
(d) At what rate must the remaining excess energy be eliminated…
Because of its metabolic processes, your body
continually emits thermal energy. Suppose that the
air in your bedroom absorbs all of this thermal
energy during the time you sleep at night (8.0
hours). Assume your metabolic rate to be
P = 80 J/s.
Chapter 19 Solutions
Physics for Scientists and Engineers with Modern Physics
Ch. 19.2 - Prob. 19.1QQCh. 19.3 - Prob. 19.2QQCh. 19.5 - Prob. 19.3QQCh. 19.5 - Characterize the paths in Figure 19.12 as...Ch. 19.6 - Prob. 19.5QQCh. 19 - Prob. 1PCh. 19 - The highest waterfall in the world is the Salto...Ch. 19 - Prob. 3PCh. 19 - The temperature of a silver bar rises by 10.0C...Ch. 19 - You are working in your kitchen preparing lunch...
Ch. 19 - If water with a mass mk at temperature Tk is...Ch. 19 - Prob. 7PCh. 19 - An electric drill with a steel drill bit of mass m...Ch. 19 - Prob. 9PCh. 19 - How much energy is required to change a 40.0-g ice...Ch. 19 - Prob. 11PCh. 19 - Prob. 12PCh. 19 - In an insulated vessel, 250 g of ice at 0C is...Ch. 19 - Prob. 14PCh. 19 - One mole of an ideal gas is warmed slowly so that...Ch. 19 - (a) Determine the work done on a gas that expands...Ch. 19 - A thermodynamic system undergoes a process in...Ch. 19 - Prob. 18PCh. 19 - A 2.00-mol sample of helium gas initially at 300...Ch. 19 - (a) How much work is done on the steam when 1.00...Ch. 19 - A 1.00-kg block of aluminum is warmed at...Ch. 19 - In Figure P19.22, the change in internal energy of...Ch. 19 - Prob. 23PCh. 19 - A concrete slab is 12.0 cm thick and has an area...Ch. 19 - Two lightbulbs have cylindrical filaments much...Ch. 19 - Prob. 26PCh. 19 - (a) Calculate the R-value of a thermal window made...Ch. 19 - Prob. 28PCh. 19 - Gas in a container is at a pressure of 1.50 atm...Ch. 19 - Prob. 30APCh. 19 - You have a particular interest in automobile...Ch. 19 - Prob. 32APCh. 19 - Prob. 33APCh. 19 - Prob. 34APCh. 19 - Review. Following a collision between a large...Ch. 19 - Prob. 36APCh. 19 - An ice-cube tray is filled with 75.0 g of water....Ch. 19 - Prob. 38APCh. 19 - An iron plate is held against an iron wheel so...Ch. 19 - One mole of an ideal gas is contained in a...Ch. 19 - Prob. 41APCh. 19 - Prob. 42APCh. 19 - Prob. 43APCh. 19 - A student measures the following data in a...Ch. 19 - (a) The inside of a hollow cylinder is maintained...Ch. 19 - Prob. 46CPCh. 19 - Prob. 47CP
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
- 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.arrow_forward(a) How long will the energy in a 1470kJ (350kcal) cup of yogurt last in a woman doing work at the rate of 150 W with an efficiency of 20.0% (such as in leisurely climbing stairs)? (b) Does the time found in part (a) imply that it is easy to consume more food energy than you can reasonably expect to work off with exercise?arrow_forward(a) If you toss 10 coins, what percent of the time will you get the three most likely macrostates (6 heads and 4 tails, 5 heads and 5 tails, 4 heads and 6 tails)? (b) You can realistically toss 10 coins and count the number of heads and tails about twice a minute. At mat rate, how long will it take on average to get either 10 heads and 0 tails or 0 heads and 10 tails?arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- College PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningCollege PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage Learning
- Physics for Scientists and Engineers, Technology ...PhysicsISBN:9781305116399Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
College Physics
Physics
ISBN:9781305952300
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781285737027
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
Physics for Scientists and Engineers, Technology ...
Physics
ISBN:9781305116399
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Thermodynamics: Crash Course Physics #23; Author: Crash Course;https://www.youtube.com/watch?v=4i1MUWJoI0U;License: Standard YouTube License, CC-BY