- A. General Materials & Mathematics
- B. Statics
- C. Kinematics & Dynamics
- D. Rotational Mechanics
- E. Gravitation & Astronomy
- F. Fluid Mechanics
- G. Vibrations & Mechanical Waves
- H. Sound
- I. Thermodynamics
- J. Electrostatics & Magnetostatics
- K. Electromagnetic Principles
- L. Geometrical Optics
- M. Wave Optics
- N. Spectra & Color
- O. Vision
- P. Modern Physics
I4-34. Hand Warmer
To demonstrate the heat of fusion.
Before re-using this gizmo, it must be boiled to put the heat back into the sodium acetate and change it back into a liquid.
A plastic bag contains a supersaturated solution of sodium acetate. When fusion is commenced by clicking a metal disc in the solution or by some other shock, the liquid quickly becomes solid, producing a large amount of heat.