How Cold Is Cold: Examining the Properties of Materials at Lower Temperatures
How Cold Is Cold: Examining the Properties of Materials at Lower TemperaturesEnglish
This video is the second lesson in the How Cold Is Cold? BLOSSOMS series and examines the properties of materials under low temperature conditions. The video consists of a series of fascinating demonstrations with liquid nitrogen, which boils at 77K (-196°C; -321°F). These demonstrations include the following:
- What goes up, may not come down.
- Is that supposed to be cold? - thermal insulation.
- Some properties of liquid nitrogen.
- Making ice cream - the slow way and the fast way.
- Try not to explode: expansion of liquid nitrogen and the ideal gas law.
- Making the air cold: phase changes and the affect on volume.
- No frozen fingers: the changes in mechanical properties.
- Resistivity at 77K.
- The magic magnet: the Meissner Effect.
- Cautions in using liquid nitrogen
Rick McMaster received his Ph.D. in low temperature physics from the University of Connecticut and is a licensed professional engineer in Electrical and Computer Engineering. Rick has had a range of assignments in his career at IBM, including process development, processor and subsystem design, marketing and business process development. Currently he is the STEM Advocate in IBM's University Programs Worldwide. He chairs the Central Texas Discover Engineering outreach to schools and is on the advisory board of WGBH's Design Squad Nation and WNET's Cyberchase.
Additional Online Resources
JLab: Frostbite Theater
This site presents short videos of liquid nitrogen experiments and is presented by the Frostbite Theater of the Jefferson Laboratory, which sponsors a collection of science videos.
How It Works: Video: The Meissner effect
This site presents a discussion of the Meissner Effect and is sponsored by How It Works: the Magazine that Feeds Minds.
Explain That Stuff! Superconductors
This site provides a clear, accessible discussion of superconductors sponsored by Explain that Stuff: the Free Online Science and Technology Book.