A 490-W heating coil designed to operate from 110 V is made of Nichrome wire 0.420 mm in diameter. (Assume ρ = 1.50 10-6 Ω · m, and α = 4.000 10-4(°C)−1 for Nichrome.) (a) Assuming the resistivity of the Nichrome remains constant at its 20.0°C value, find the length of wire used. m (b) Now consider the variation of resistivity with temperature. What power is delivered to the coil of part (a) when it is warmed to 1 200°C?

A 490-W heating coil designed to operate from 110 V is made of Nichrome wire 0.420 mm in diameter. (Assume ρ = 1.50 10-6 Ω · m, and α = 4.000 10-4(°C)−1 for Nichrome.) (a) Assuming the resistivity of the Nichrome remains constant at its 20.0°C value, find the length of wire used. m (b) Now consider the variation of resistivity with temperature. What power is delivered to the coil of part (a) when it is warmed to 1 200°C?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 17CQ: Resistors are commonly rated at 18W,14W,12W ,1 W and 2 W for use in electrical circuits. If a...

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