Principles of Physics: A Calculus-Based Text
5th Edition
ISBN: 9781133104261
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 18, Problem 4OQ
To determine
The change in the average temperature of the apartment.
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A window air conditioner is placed on a table inside a well-insulated apartment, plugged in and turned on. What happens to the average temperature of the apartment? (a) It increases. (b) It decreases. (c) It remains constant. (d) It increases until the unit warms up and then decreases. (e) The answer depends on the initial temperature of the apartment.
No heat losses exist in this task.
Hampus is concerned about the expensive electricity price. Stingy as he is, he tells his daughter that she is not allowed to bathe in the bathtub. Assume that the water temperature entering the house is 5.0°C. For the bath to be pleasant, the bath water must be 38°C.
a) How much energy is needed to heat the water to 38°C in a bathtub of size 0.150 m³?
b) How long does it take for the water heater to heat 0.150 m³ of water from 5.0°C to 38°C if it has an output of 1.0kW and an efficiency of n = 0.80 ?
c) How much does a bath cost if the electricity price for 1 kWh is $5?
Hampu's daughter does not care about the electricity price, so she pours a bath when Hampu is not at home. Unfortunately, the bath water is 45°C, so she adds cold water until the water is 38°C.
d) How much 5°C cold water does she need to fill in the bathtub for the mixture to become 38°C?
What does the third law of thermodynamics sound like?
In a solar water heater, energy from the Sun is gathered by water that circulates through tubes in a rooftop collector.The solar radiation enters the collector through a transparent cover and warms the water in the tubes; this water is pumped into a holding tank. Assume that the efficiency of the overall system is 20% (that is, 80% of the incident solar energy is lost from the system). What collector area is necessary to raise the temperature of 200 L of water in the tank from 20C to 40°C in 1.0 h when the intensity of incident sunlight is 700 W/m2?
Chapter 18 Solutions
Principles of Physics: A Calculus-Based Text
Ch. 18.1 - The energy input to an engine is 3.00 times...Ch. 18.3 - Prob. 18.2QQCh. 18.4 - Prob. 18.3QQCh. 18.6 - (a) Suppose you select four cards at random from a...Ch. 18.7 - Which of the following is true for the entropy...Ch. 18.7 - An ideal gas is taken from an initial temperature...Ch. 18.8 - True or False: The entropy change in an adiabatic...Ch. 18 - Prob. 1OQCh. 18 - Prob. 2OQCh. 18 - A refrigerator has 18.0 kJ of work done on it...
Ch. 18 - Prob. 4OQCh. 18 - Consider cyclic processes completely characterized...Ch. 18 - Prob. 6OQCh. 18 - Prob. 7OQCh. 18 - Prob. 8OQCh. 18 - A sample of a monatomic ideal gas is contained in...Ch. 18 - Assume a sample of an ideal gas is at room...Ch. 18 - Prob. 11OQCh. 18 - Prob. 1CQCh. 18 - Prob. 2CQCh. 18 - Prob. 3CQCh. 18 - Prob. 4CQCh. 18 - Prob. 5CQCh. 18 - Prob. 6CQCh. 18 - Prob. 7CQCh. 18 - Prob. 8CQCh. 18 - Prob. 9CQCh. 18 - Prob. 10CQCh. 18 - Prob. 11CQCh. 18 - Discuss three different common examples of natural...Ch. 18 - The energy exhaust from a certain coal-fired...Ch. 18 - Prob. 1PCh. 18 - Prob. 2PCh. 18 - Prob. 3PCh. 18 - Prob. 4PCh. 18 - Prob. 5PCh. 18 - Prob. 6PCh. 18 - Prob. 7PCh. 18 - Prob. 8PCh. 18 - Prob. 9PCh. 18 - Prob. 10PCh. 18 - Prob. 11PCh. 18 - Prob. 12PCh. 18 - Prob. 13PCh. 18 - Prob. 14PCh. 18 - Argon enters a turbine at a rate of 80.0 kg/min, a...Ch. 18 - Prob. 16PCh. 18 - A refrigerator has a coefficient of performance...Ch. 18 - Prob. 18PCh. 18 - Prob. 19PCh. 18 - In 1993, the U.S. government instituted a...Ch. 18 - Prob. 21PCh. 18 - Prob. 22PCh. 18 - Prob. 23PCh. 18 - Prob. 24PCh. 18 - A heat pump used for heating shown in Figure...Ch. 18 - Prob. 26PCh. 18 - Prob. 27PCh. 18 - An ice tray contains 500 g of liquid water at 0C....Ch. 18 - Prob. 29PCh. 18 - Prob. 30PCh. 18 - Prob. 31PCh. 18 - (a) Prepare a table like Table 18.1 for the...Ch. 18 - Prob. 33PCh. 18 - Prob. 34PCh. 18 - Prob. 35PCh. 18 - Prob. 36PCh. 18 - Prob. 37PCh. 18 - Prob. 38PCh. 18 - Prob. 39PCh. 18 - Prob. 40PCh. 18 - Prob. 41PCh. 18 - Prob. 42PCh. 18 - (a) Find the kinetic energy of the moving air in a...Ch. 18 - Prob. 45PCh. 18 - Prob. 46PCh. 18 - Prob. 47PCh. 18 - An idealized diesel engine operates in a cycle...Ch. 18 - Prob. 49PCh. 18 - Prob. 50PCh. 18 - Prob. 51PCh. 18 - Prob. 52PCh. 18 - Prob. 53PCh. 18 - Prob. 54PCh. 18 - Prob. 55PCh. 18 - Prob. 56PCh. 18 - Prob. 57PCh. 18 - Prob. 58PCh. 18 - Prob. 59PCh. 18 - Prob. 60PCh. 18 - Prob. 61PCh. 18 - Prob. 62PCh. 18 - A 1.00-mol sample of an ideal monatomic gas is...Ch. 18 - Prob. 64PCh. 18 - Prob. 65P
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