The radius of a piece of Nichrome wire is 0.306 mm. (Assume the wire's temperature is 20°C.) (a) Calculate the resistance per unit length of this wire. SOLUTION Conceptualize This table shows that Nichrome has a resistivity two orders of magnitude larger than the best conductors in the table. Therefore, we expect it to have some special practical applications that the best conductors may not have. .... Categorize We model the wire as a --Select- e so that a simple geometric analysis can be applied to find the resistance. Analyze Use this equation and the resistivity of Nichrome to find the resistance per unit length (in 0/m): R. 0/m %3D A. (b) If a potential difference of 10 V is maintained across a 1.0 m length of the Nichrome wire, what is the current in the wire? SOLUTION Analyze Use this equation to find the current (in A): AV R

The radius of a piece of Nichrome wire is 0.306 mm. (Assume the wire's temperature is 20°C.) (a) Calculate the resistance per unit length of this wire. SOLUTION Conceptualize This table shows that Nichrome has a resistivity two orders of magnitude larger than the best conductors in the table. Therefore, we expect it to have some special practical applications that the best conductors may not have. .... Categorize We model the wire as a --Select- e so that a simple geometric analysis can be applied to find the resistance. Analyze Use this equation and the resistivity of Nichrome to find the resistance per unit length (in 0/m): R. 0/m %3D A. (b) If a potential difference of 10 V is maintained across a 1.0 m length of the Nichrome wire, what is the current in the wire? SOLUTION Analyze Use this equation to find the current (in A): AV R