(a).i. An electric heating element to dissipate 580W on 240V is to be made from nichrome ribbon 1mm wide and thickness of 0.005mm. Calculate the length of the ribbon required if the resistivity of nichrome is 1.1x 10-6Ωm. ii. The resistance of a coil aluminum wire at 21OC is 210Ω. The temperature of the wire is increased and the resistance rises to 240Ω. If the coefficient of resistance of aluminum is 0 .0039/OC at 21OC, determine the temperature to which the coil has risen.

(a).i. An electric heating element to dissipate 580W on 240V is to be made from nichrome ribbon 1mm wide and thickness of 0.005mm. Calculate the length of the ribbon required if the resistivity of nichrome is 1.1x 10-6Ωm. ii. The resistance of a coil aluminum wire at 21OC is 210Ω. The temperature of the wire is increased and the resistance rises to 240Ω. If the coefficient of resistance of aluminum is 0 .0039/OC at 21OC, determine the temperature to which the coil has risen.

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter16: Installation Of Heating, Cooling, And Refrigeration Systems

Section: Chapter Questions

Problem 2RQ

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