= P = A circuit is shaped like an equilateral triangle with side length L 75 cm. The wiring that is used has a radius of r = 0.40 mm and a resistivity of 1.1 × 10-6 m. The circuit contains an ideal battery, whose voltage has been ad- justed so that the circuit is dissipating energy at a rate of P = 25 W. The battery is small compared to the circuit's length, so that the total length of wiring can be approximated as the perimeter of the triangle. What is the average cur- rent density J in the wiring? For the representation, make sure to draw a circuit diagram as well as a cross-section of the wiring with the radius and the direction of current clearly indicated. For the limit check, investigate what happens to J as the wiring becomes extremely skinny (i.e., r → 0) while all other given quantities remain the same. Initial Equations Algebra Work (Symbols only. Don't plug in any numbers yet.) Symbolic Answer: Unit Check Limit Check a) Asr 0, what limit does J approach? b) Why does the result make physical sense? Numerical Answer: (Obtain this by plugging numbers into your symbolic answer.)

= P = A circuit is shaped like an equilateral triangle with side length L 75 cm. The wiring that is used has a radius of r = 0.40 mm and a resistivity of 1.1 × 10-6 m. The circuit contains an ideal battery, whose voltage has been ad- justed so that the circuit is dissipating energy at a rate of P = 25 W. The battery is small compared to the circuit's length, so that the total length of wiring can be approximated as the perimeter of the triangle. What is the average cur- rent density J in the wiring? For the representation, make sure to draw a circuit diagram as well as a cross-section of the wiring with the radius and the direction of current clearly indicated. For the limit check, investigate what happens to J as the wiring becomes extremely skinny (i.e., r → 0) while all other given quantities remain the same. Initial Equations Algebra Work (Symbols only. Don't plug in any numbers yet.) Symbolic Answer: Unit Check Limit Check a) Asr 0, what limit does J approach? b) Why does the result make physical sense? Numerical Answer: (Obtain this by plugging numbers into your symbolic answer.)

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 40P: Four resistors are connected to a battery as shown in Figure P21.40. The current in the battery is...

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