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Question
The resistance of a nichrome wire at 0°C is 10Ω. If its temperature coefficient of resistivity of nichrome is 0.004/ °C, find its resistance of the wire at boiling point of water. Comment on the result.
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Solution
Given data:
R0 = 10Ω
The boiling point of water T = 100°C
α = 0.004°C
RT = ?
Formula:
RT = R0 [l + αT)]
RT = 10 [1 + (0.004 × 100)]
= 10(1 + 0.4)
= 10 (1.4)
RT = 14Ω
As the temperature increase the resistance of the wire also increases.
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