25.25 • (a) What is the resistance of a Nichrome wire at 0.0°C i its resistance is 100.00 N at 11.5°C? (b) What is the resistance of: carbon rod at 25.8°C if its resistance is 0.0160 Q at 0.0°C?

25.25 • (a) What is the resistance of a Nichrome wire at 0.0°C i its resistance is 100.00 N at 11.5°C? (b) What is the resistance of: carbon rod at 25.8°C if its resistance is 0.0160 Q at 0.0°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 32PE: An electronic device designed to operate at any temperature in the range from -10.0°C to 55.0°C...

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When a straight wire is heated, its resistance changes according to the equation R = R0 [1 + (T T0)] (Eq. 17.7), where is the temperature coefficient of resistivity. (a) Show that a more precise result, which includes the length and area of a wire change when it is heated, is R=R0[1+(TT0)][1+(TT0)][1+2(TT0)] where is the coefficient of linear expansion. (See Topic 10.) (b) Compare the two results for a 2.00-m-long copper wire of radius 0.100 mm, starting at 20.0C and heated to 100.0C.
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