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Name: Marianne
Status: Student
Age: 16
Location: N/A
Country: N/A
Date: N/A

I want to know about the resistance of a filament light bulb and a lenght of nichrome wire. I want to know what factors effect the resistance of a light bulb and of a length of nichrome wire. I would also like to know why the resistance of a nichrome wire is constant and the resistance of a filament bulb will be varied.

The resistance of the nichrome wire depends on cross sectional area, length, crystalline structure and purity, and temperature. For a wire of constant manufacture, all of these variables remain the same, so the resistance is constant. If you heat it as the filament of a lightbulb, the temperature changes, and therefore, the resistance changes.

Nathan A. Unterman

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