University Physics with Modern Physics (14th Edition)
14th Edition
ISBN: 9780321973610
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Textbook Question
Chapter 25, Problem 25.76P
DATA According to the U.S. National Electrical Code, copper wire used for interior wiring of houses, hotels, office buildings, and industrial plants is permitted to carry no more than a specified maximum amount of current. The table shows values of the maximum current Imax for several common sizes of wire with varnished cambric insulation. The “wire gauge” is a standard used to describe the diameter of wires. Note that the larger the diameter of the wire, the smaller the wire gauge.
(a) What considerations determine the maximum current-carrying capacity of household wiring? (b) A total of 4200 W of power is to be supplied through the wires of a house to the household electrical appliances. If the potential difference across the group of appliances is 120 V, determine the gauge of the thinnest permissible wire that can be used, (c) Suppose the wire used in this house is of the gauge found in part (b) and has total length 42.0 m. At what rate is energy dissipated in the wires? (d) The house is built in a community where the consumer cost of electrical energy is $0.11 per kilowatt-hour. If the house were built with wire of the next larger diameter than that found in part (b), what would be the savings in electricity costs in one year? Assume that the appliances are kept on for an average of 12 hours a day.
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Chapter 25 Solutions
University Physics with Modern Physics (14th Edition)
Ch. 25.1 - Suppose we replaced the wire in Example 25.1 with...Ch. 25.2 - Prob. 25.2TYUCh. 25.3 - Suppose you increase the voltage across the copper...Ch. 25.4 - Rank the following circuits in order from highest...Ch. 25.5 - Rank the following circuits in order from highest...Ch. 25.6 - Which of the following factors will, if increased,...Ch. 25 - The definition of resistivity ( = E/J) implies...Ch. 25 - A cylindrical rod has resistance R. If we triple...Ch. 25 - A cylindrical rod has resistivity . If we triple...Ch. 25 - Two copper wires with different diameters are...
Ch. 25 - When is a 1.5-V AAA battery not actually a 1.5-V...Ch. 25 - Can the potential difference between the terminals...Ch. 25 - A rule of thumb used to determine the internal...Ch. 25 - Batteries are always labeled with their emf; for...Ch. 25 - We have seen that a coulomb is an enormous amount...Ch. 25 - Electrons in an electric circuit pass through a...Ch. 25 - Temperature coefficients of resistivity are given...Ch. 25 - Which of the graphs in Fig. Q25.12 best...Ch. 25 - Why does an electric light bulb nearly always burn...Ch. 25 - A light bulb glows because it has resistance. The...Ch. 25 - (See Discussion Question Q25.14.) An ideal ammeter...Ch. 25 - (See Discussion Question Q25.14.) Will a light...Ch. 25 - The energy that can be extracted from a storage...Ch. 25 - Eight flashlight batteries in series have an cmf...Ch. 25 - Small aircraft often have 24-V electrical systems...Ch. 25 - Long-distance, electric-power, transmission lines...Ch. 25 - Ordinary household electric lines in North America...Ch. 25 - A fuse is a device designed to break a circuit,...Ch. 25 - High-voltage power supplies are sometimes designed...Ch. 25 - The text states that good thermal conductors are...Ch. 25 - Lightning Strikes. During lightning strikes from a...Ch. 25 - A silver wire 2.6 mm in diameter transfers a...Ch. 25 - A 5.00-A current runs through a 12-gauge copper...Ch. 25 - An 18-gauge copper wire (diameter 1.02 mm) carries...Ch. 25 - Copper has 8.5 1028 free electrons per cubic...Ch. 25 - Prob. 25.6ECh. 25 - CALC The current in a wire varies with time...Ch. 25 - Current passes through a solution of sodium...Ch. 25 - BIO Transmission of Nerve Impulses. Nerve cells...Ch. 25 - (a) At room temperature, what is the strength of...Ch. 25 - A 1.50-m cylindrical rod of diameter 0.500 cm is...Ch. 25 - A copper wire has a square cross section 2.3 mm on...Ch. 25 - Prob. 25.13ECh. 25 - Prob. 25.14ECh. 25 - A cylindrical tungsten filament 15.0 cm long with...Ch. 25 - A ductile metal wire has resistance R. What will...Ch. 25 - Prob. 25.17ECh. 25 - Prob. 25.18ECh. 25 - Prob. 25.19ECh. 25 - Prob. 25.20ECh. 25 - A current-carrying gold wire has diameter 0.84 mm....Ch. 25 - A hollow aluminum cylinder is 2.50 m long and has...Ch. 25 - Prob. 25.23ECh. 25 - A carbon resistor is to be used as a thermometer....Ch. 25 - A copper transmission cable 100 km long and 10.0...Ch. 25 - Consider the circuit shown in Fig. E25.26. The...Ch. 25 - An ideal voltmeter V is connected to a 2.0-11...Ch. 25 - An idealized ammeter is connected to a battery as...Ch. 25 - When switch S in Fig. E25.29 is open, the...Ch. 25 - The circuit shown in Fig. E25.30 contains two...Ch. 25 - In the circuit shown in Fig. E25.30, the 16.0-V...Ch. 25 - In the circuit of Fig. E25.30, the 5.0- resistor...Ch. 25 - The circuit shown in Fig. E25.33 contains two...Ch. 25 - When a resistor with resistance R is connected to...Ch. 25 - Light Bulbs. The power rating of a light bulb...Ch. 25 - If a 75-W" bulb (see Problem 25.35) is connected...Ch. 25 - European Light Bulb. In Europe the standard...Ch. 25 - A battery-powered global positioning system (GPS)...Ch. 25 - Consider the circuit of Fig. E25.30. (a) What is...Ch. 25 - BIO Electric Eels. Electric eels generate electric...Ch. 25 - BIO Treatment of Heart Failure. A heart...Ch. 25 - The battery for a certain cell phone is rated at...Ch. 25 - Prob. 25.43ECh. 25 - An idealized voltmeter is connected across the...Ch. 25 - A 25.0- bulb is connected across the terminals of...Ch. 25 - A typical small flashlight contains two batteries,...Ch. 25 - In the circuit in Fig. E25.47, find (a) the rate...Ch. 25 - A 540-W electric heater is designed to operate...Ch. 25 - Prob. 25.49ECh. 25 - In an ionic solution, a current consists of Ca2+...Ch. 25 - An electrical conductor designed to carry large...Ch. 25 - An overhead transmission cable for electrical...Ch. 25 - On your first day at work as an electrical...Ch. 25 - A 2.0-m length of wire is made by welding the end...Ch. 25 - A 3.00-m length of copper wire at 20 C has a...Ch. 25 - A heating clement made of tungsten wire is...Ch. 25 - CP BIO Struck by Lightning. Lightning strikes can...Ch. 25 - A resistor with resistance R is connected to a...Ch. 25 - CALC A material of resistivity is formed into a...Ch. 25 - CALC The region between two concentric conducting...Ch. 25 - The potential difference across the terminals of a...Ch. 25 - (a) What is the potential difference Vad in the...Ch. 25 - BIO The average bulk resistivity of the human body...Ch. 25 - BIO A person with body resistance between his...Ch. 25 - A typical cost for electrical power is 0,120 per...Ch. 25 - In the circuit shown in Fig. P25.66, R is a...Ch. 25 - A Nonideal Ammeter. Unlike the idealized ammeter...Ch. 25 - A cylindrical copper cable 1.50 km long is...Ch. 25 - CALC A 1.50-m cylinder of radius 1.10 cm is made...Ch. 25 - Compact Fluorescent Bulbs. Compact fluorescent...Ch. 25 - Prob. 25.71PCh. 25 - CP Consider the circuit shown in Fig. P25.72. The...Ch. 25 - CP Consider the circuit shown in Fig. P25.73. The...Ch. 25 - DATA An external resistor R is connected between...Ch. 25 - DATA The voltage drop Vab across each of resistors...Ch. 25 - DATA According to the U.S. National Electrical...Ch. 25 - Prob. 25.77CPCh. 25 - An external resistor with resistance R is...Ch. 25 - BIO SPIDERWEB CONDUCTIVITY. Some types of spiders...Ch. 25 - BIO SPIDERWEB CONDUCTIVITY. Some types of spiders...Ch. 25 - BIO SPIDERWEB CONDUCTIVITY. Some types of spiders...Ch. 25 - BIO SPIDERWEB CONDUCTIVITY. Some types of spiders...
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