Eg-2 Temperature Dependence of Resistance
Aim
To demonstrate that the resistance of a copper wire depends on the temperature.
Apparatus
- Liquid Nitrogen
- Dewar Flask
- 0-14V DC Power Supply
- Resistance coil apparatus
Description
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.