A cylindrical rod 1.50 m long and 0.500 cm in diameter is connected to a power source that maintains a constant potential difference of 15.0 V between its ends, while an ammeter measures the current through it. It is observed that at room temperature (20.0 °C) the ammeter gives a reading of 18.5 A, while at 92.0 °C it gives a reading of 17.2 A. The thermal expansion of the rod can be ignored. Calculate: a) the resistivity and b) the temperature coefficient of resistivity at 20 °C for the rod material.

A cylindrical rod 1.50 m long and 0.500 cm in diameter is connected to a power source that maintains a constant potential difference of 15.0 V between its ends, while an ammeter measures the current through it. It is observed that at room temperature (20.0 °C) the ammeter gives a reading of 18.5 A, while at 92.0 °C it gives a reading of 17.2 A. The thermal expansion of the rod can be ignored. Calculate: a) the resistivity and b) the temperature coefficient of resistivity at 20 °C for the rod material.

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter27: Current And Resistance

Section: Chapter Questions

Problem 27.73AP

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