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Ch 25: Current, Resistance, and EMF
Young & Freedman Calc - University Physics 14th Edition
Young & Freedman Calc14th EditionUniversity PhysicsISBN: 9780321973610Non è quello che usi tu?Cambia libro di testo
Capitolo 25, Problema 23b

What is the resistance of a carbon rod at 25.825.8°C if its resistance is 0.0160Ω0.0160 Ω at 0.00.0°C?

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Identify the formula for resistance change with temperature: \( R = R_0 (1 + \alpha \Delta T) \), where \( R \) is the resistance at temperature \( T \), \( R_0 \) is the resistance at the reference temperature, \( \alpha \) is the temperature coefficient of resistance, and \( \Delta T \) is the change in temperature.
Determine the known values: \( R_0 = 0.0160 \; \Omega \) at \( 0.0^\circ C \), \( T = 25.8^\circ C \), and \( \Delta T = 25.8^\circ C - 0.0^\circ C = 25.8^\circ C \).
Look up the temperature coefficient of resistance for carbon, which is typically around \( \alpha = -0.0005 \; ^\circ C^{-1} \).
Substitute the known values into the formula: \( R = 0.0160 \; \Omega (1 + (-0.0005 \; ^\circ C^{-1}) \times 25.8^\circ C) \).
Simplify the expression to find the resistance \( R \) at \( 25.8^\circ C \).

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Resistance

Resistance is a measure of the opposition to the flow of electric current through a conductor. It is influenced by the material's properties, length, and cross-sectional area. The unit of resistance is the ohm (Ω), and it plays a crucial role in determining how much current will flow for a given voltage according to Ohm's Law.
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