Residential building codes typically require the use of 12-gauge copper wire (diameter 0.205 cm) for wiring receptacles. Such circuits carry currents as large as 20.0 A. If a wire of smaller diameter (with a higher gauge number) carried that much current, the wire could rise to a high temperature and cause a fire. (Table of resistivities) (a) Calculate the rate at which internal energy is produced in 1.95 m of 12-gauge copper wire carrying a current of 20.0 A. 0.000000040 x If you know the resistance of a wire, how do you calculate the rate at which internal energy is produced for a given current? W (b) Repeat the calculation for a 12-gauge aluminum wire. w

Residential building codes typically require the use of 12-gauge copper wire (diameter 0.205 cm) for wiring receptacles. Such circuits carry currents as large as 20.0 A. If a wire of smaller diameter (with a higher gauge number) carried that much current, the wire could rise to a high temperature and cause a fire. (Table of resistivities) (a) Calculate the rate at which internal energy is produced in 1.95 m of 12-gauge copper wire carrying a current of 20.0 A. 0.000000040 x If you know the resistance of a wire, how do you calculate the rate at which internal energy is produced for a given current? W (b) Repeat the calculation for a 12-gauge aluminum wire. w

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter21: Current And Direct Current Circuits

Section: Chapter Questions

Problem 61P

See similar textbooks

Similar questions

In the United States, the National ElectricCode sets standards for maximum safe currents in insulated copperwires of various diameters. The accompanying table gives a portionof the code. Notice that wire diameters are identified by the gauge ofthe wire, and that 1 mil = 10-3in. Find the maximum power dissipated per length in (a) an 8-gauge wire and (b) a 10-gauge wire.Gauge Diameter (mils) Safe current (A)8 129 3510 102 25
Residential building codes typically require the use of 12-gauge copper wire (diameter 0.205 cm) for wiring receptacles. Such circuits carry currents as large as 20.0 A. If a wire of smaller diameter (with a higher gauge number) carried that much current, the wire could rise to a high temperature and cause a fire. (a) Calculate the rate at which internalenergy is produced in 1.00 m of 12-gauge copper wire carrying 20.0 A. (b) What If? Repeat the calculation for a 12-gauge aluminum wire. (c) Explain whether a 12-gauge aluminum wire would be as safe as a copper wire.
A 12.0-V emf automobile battery has a terminal voltage of 16.0 V when being charged by a current of 10.0 A. (a) What is the battery’s internal resistance? (b) What power is dissipatedinside the battery? (c) At what rate (in ºC/min ) will itstemperature increase if its mass is 20.0 kg and it has aspecific heat of 0.300 kcal/kg ⋅ ºC , assuming no heatescapes?
What current flows through a 2.54-cm-diameter rod of pure silicon that is 20.0 cm long, when 1.00 X 103 V is applied to it? (Such a rod may be used to make nuclear-particle detectors, for example.)
Consider a portable electric blanket that runs on a 4.5 V battery. If you use copper wire with a 0.5 mm diameter as the heating element, how long should the wire be (in unit of meters) if you want to generate 15 W of heating power? (Take the resistivity of the copper wire as p= 1.7 x 10^(-8) Ω.m)
A lightning flash during a thunderstorm can consist of one to tens of individual strokes, each with a duration between 10 and 100 milliseconds. Peak currents in a stroke can be as high as 20 kiloamperes. If a specific lightning flash has 10 separate strokes each lasting 50 milliseconds and carrying an average current of 8 kiloamperes, about how much charge gets transferred from the earth to the sky or vice versa? (Hint: the answer provided is 4000 C)
A 14-gauge copper wire has a diameter of 1.628 mm. What magnitude current flows when the drift velocity is 1.00 mm/s? (See below example for useful information.) Calculate the drift velocity of electrons in a 12-gauge copper wire (which has a diameter of 2.053 mm) carrying a 20.0-A current, given that there is one free electron per copper atom. (Household wiring often contains 12-gauge copper wire, and the maximum current allowed in such wire is usually 20 A.) The density of copper is 8.80 x 103 kg/m3 .
Saltwater in a cylindrical rubber hose has resistivity of 5.0 Ω·m. Calculate the factor by which theresistance of the water changes when the hose is stretched so that its length increases by a factorof 1.4. The water volume remains constant.
What current flows through a 2.54-cm-diameter rod of pure silicon that is 20.0 cm long, when 1.00 × 103 V is applied to it? (Such a rod may be used to make nuclear- particle detectors, for example.)
The temperature in Philadelphia, PA can vary between 68.00 °F and 100.00 °F in one summer day. By what percentage will an aluminum wire’s resistance change during the day?
An electronic device designed to operate at any temperature in the range from −10.0 °C to 55.0 °C contains pure carbon resistors. By what factor does their resistance increase over this range?
A cylindrical resistor of radius 5.0 mm and length 2.0 cm is made of material that has a resistivity of 3.5 * 10-5 ohm m.What are (a) the magnitude of the current density and (b) the potential difference when the energy dissipation rate in the resistor is 1.0W?