1. A block made of a material with a resistivity p, has length L and its cross section is square with side dimensions decreasing linearly (from a to b). Assume that the current density is uniform across any cross section taken perpendicular to the length. a a) Find the resistance of the block. b) Verify that for a = b, you recover the resistance for a prism (R=PL, c) What is the rate of the energy dissipated as thermal energy on this resistor if it is connected to a potential difference of V across its terminals? a

1. A block made of a material with a resistivity p, has length L and its cross section is square with side dimensions decreasing linearly (from a to b). Assume that the current density is uniform across any cross section taken perpendicular to the length. a a) Find the resistance of the block. b) Verify that for a = b, you recover the resistance for a prism (R=PL, c) What is the rate of the energy dissipated as thermal energy on this resistor if it is connected to a potential difference of V across its terminals? a

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 81CP: A 10-gauge copper wire has a cross-sectional area A=5.26mm2 and carries a current of I=5.00A . The...

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