How cold can STUFF get? Theory tells us that the very lowest we can EVER hope to get is -273 C - called Absolute Zero. But who really knows? It might be lower somewhere in this Universe! For ordinary ad¬ventures we can get the following:
Ice and salt -20°C or so.
Dry Ice and alcohol -78.5°C or so.
Liquid Nitrogen -195°C.
And this is pretty cold — as we shall see.

A. A teakettle filled with liquid nitrogen boils on a cake of ice!

B. And now we proceed with a number of things - all showing how
this VERY COLD STUFF changes the properties of ordinary things:
a. We freeze a "hot dog".
b. We freeze an onion.
c. A lead spring which is : lifeless" at room temperatures becomes
VERY SPRINGY AND ELASTIC.
d. A rubber ball which bounces at room temperature becomes
frightfully brittle when made so cold.
e. A lead plate which hardly "sings" at room temperature emits a
beautiful high note when very cold. It becomes elastic.
f. A lamp lights so bright - or dim - at room temperature.
We lower the temperature of the coil connected to it. The lamp now flares up. WHY? The electrical resistance of conductors goes down with drop in temperature. . .so the electrical conductivity is higher.

Thus we see that the properties which STUFF possesses changes with the temperature. An understanding of this is very important. The pistons in your automobile engine get very hot. Space vehicles get very cold. On the Moon - with no atmosphere - as we now believe - you could stand at the very edge of light and dark and freeze one side of you and boil the other.

1. The Idea of the Center of Gravity
2. Newton's First Law of Motion: Inertia
3. Newton's Second Law of Motion: The Elevator Problem
4. Newton's Third Law of Motion: Momentum
5. Energy and Momentum
6. Concerning Falling Bodies & Projectiles
7. The Simple Pendulum and Other Oscillating Things
8. Adventures with Bernoulli: Bernoulli's Principle
9. Soap Bubbles and Soap Films
10. Atmospheric Pressure
11. Centrifugal Force and Other Strange Matters
12. The Strange Behavior of Rolling Things
13. Archimedes' Principle
14. Pascal's Principle: The Properties of Liquids
15. Levers, Inclines Planes, Geared-wheels and Other Machines
16. The Ideas of Heat and Temperature
17. Thermometric Properties and Processes
18. How to Produce Heat Energy
19. Thermal Expansion of Stuff: Solids
20. Thermal Expansion of Stuff: Gases & Liquids
21. The Strange Thermal Behavior of Ice and Water
22. Heat Energy Transfer by Conduction
23. Heat Energy Transfer by Convection
24. Heat Energy Transfer by Radiation
25. Evaporation, Boiling, Freezing: A Dramatic Adventure
26. Miscellaneous Adventures in Heat
27. The Drama in Real Cold Stuff: Liquid Nitrogen
28. The Physics of Toys: Mechanical
29. The Physics of Toys: Acoustic and Thermal
30. Waves: Kinds of Properties
31. Sound Waves: Sources of Sound & Pitch and Frequency
32. Vibrating Bars and Strings: The Phenomenon of Beats
33. Resonance: Forced Vibrations
34. Sounding Pipes
35. Vibrating Rods and Plates
36. Miscellaneous Adventures in Sound
37. Electrostatic Phenomena: Foundations of Electricity
38. Electrostatic Toys, Part 1
39. Electrostatic Toys, Part 2
40. Adventures with Electric Charges
41. Adventures in Magnetism
42. Ways to "Produce" Electricity
43. Properties and Effects of Electric Currents
44. Adventures in Electromagnetism
45. Further Adventures in Electromagnetism
46. Miscellaneous and Wondrous Things in E&M

Demonstrations in Physics was an educational science series produced in Australia by ABC Television in 1969. The series was hosted by American scientist Julius Sumner Miller, who demonstrated experiments involving various disciplines in the world of physics. The series was also released in the United States under the title Science Demonstrations.

This program was a series of 45 shows (approximately 15 minutes each) on various topics in physics, organized into 3 units: Mechanics; Heat and Temperature / Toys; and Waves and Sound / Electricity and Magnetism.