QUESTION In comparing wires of identical shape and carrying the same current but made of different metals, is the drift velocity in each wire inversely proportional to the number density of charge carriers? O No. The drift velocity is directly proportional to the number density of carriers. Yes. To have the same current from k times as many carriers, it takes 1/k times the drift speed. O No. The drift velocity is the same for all conductors. O Yes. To have the same current from k times as many carriers, it takes k times the drift speed. PRACTICE IT Use the worked example above to help you solve this problem. The amount of charge that passes through a filament of a certain lightbulb in 2.25 s is 1.50 C. (a) Find the current in the bulb. A (b) Find the number of electrons that pass through the filament in 5.31 s. electrons (c) If the current is supplied by a 12.0-V battery, what total energy is delivered to the lightbulb filament? J What is the average power? W

QUESTION In comparing wires of identical shape and carrying the same current but made of different metals, is the drift velocity in each wire inversely proportional to the number density of charge carriers? O No. The drift velocity is directly proportional to the number density of carriers. Yes. To have the same current from k times as many carriers, it takes 1/k times the drift speed. O No. The drift velocity is the same for all conductors. O Yes. To have the same current from k times as many carriers, it takes k times the drift speed. PRACTICE IT Use the worked example above to help you solve this problem. The amount of charge that passes through a filament of a certain lightbulb in 2.25 s is 1.50 C. (a) Find the current in the bulb. A (b) Find the number of electrons that pass through the filament in 5.31 s. electrons (c) If the current is supplied by a 12.0-V battery, what total energy is delivered to the lightbulb filament? J What is the average power? 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 16P

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Similar questions

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