A copper wheel rubs against a copper plate in such a manner that there is a 47.0 N force of kinetic friction between them, and the relative speed at which the two surfaces slide over each other is 41.0 m/s. The specific heat for copper is 387 J/(kg · °C). (a)Determine the rate at which mechanical energy is converted to internal energy (in W). W (b)If the wheel and plate each have a mass of 3.00 kg and they each receive half the internal energy from a 14.0 s run, determine the resultant temperature increase (in °C) of each after they have been given time to reach a uniform temperature.

A copper wheel rubs against a copper plate in such a manner that there is a 47.0 N force of kinetic friction between them, and the relative speed at which the two surfaces slide over each other is 41.0 m/s. The specific heat for copper is 387 J/(kg · °C). (a)Determine the rate at which mechanical energy is converted to internal energy (in W). W (b)If the wheel and plate each have a mass of 3.00 kg and they each receive half the internal energy from a 14.0 s run, determine the resultant temperature increase (in °C) of each after they have been given time to reach a uniform temperature.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter21: Heat And The First Law Of Thermodynamics

Section: Chapter Questions

Problem 71PQ

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