Eg-2 Temperature Dependence of Resistance
Published: Tuesday 14 March 2006 - Updated: Tuesday 29 March 2011
To demonstrate that the resistance of a copper wire depends on the temperature.
- Liquid Nitrogen
- Dewar Flask
- 0-14V DC Power Supply
- Resistance coil apparatus
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A coil of wire wound on a copper former is connected to a small light globe. The voltage on the power supply is adjusted till the globe glows dimly. If the copper tube is immersed in a Dewer of liquid Nitrogen the resulting change in resistance causes the globe to glow brightly.