A piece of resistance wire, 15.6 m long and of cross-sectional area 12 mm² 0 °C, passes a current of 7.9 A when connected to d.c. supply at 240 V. Calculate (a) resistivity of the wire, (b) the current which will flow when the temperature rises to 55 °C . The at temperature of temperature coefficient of the resistance wire is 0.00029 / °C.

A piece of resistance wire, 15.6 m long and of cross-sectional area 12 mm² 0 °C, passes a current of 7.9 A when connected to d.c. supply at 240 V. Calculate (a) resistivity of the wire, (b) the current which will flow when the temperature rises to 55 °C . The at temperature of temperature coefficient of the resistance wire is 0.00029 / °C.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter20: Electric Current, Resistance, And Ohm's Law

Section: Chapter Questions

Problem 1PE: What is the current in milliamperes produced by the solar cells of a pocket calculator through which...

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