When bent repeatedly, a coat hanger heats up and eventually break!
Watch The Video:
Other Demos of Interest:
 |
 |
 |
|
How a Tippe Top Works |
Coefficient of Friction |
Kinetic Friction |
Teachable Topics:
- friction
- kinetic energy
- thermal energy
Theory:
Internal friction is a force that arises from resistance between groups of particles in a solid when it is deformed. Heat is generated as a result of this deformation as kinetic energy is converted into thermal energy. This causes the material to warm up, which can be seen with an infrared camera. If enough heat is generated through prolonged deformation, the material can even break.
Apparatus:
- coat hanger
- pliers to hold hanger with (it heats up considerably and can burn you)
- infrared camera
Procedure:
- repeatedly bend a coat hanger back and forth
- after doing this you can feel the heat coming off the metal, and see it with an infrared camera (you can smell it too)
Warning: after prolonged bending, the coat hanger can get considerably hot and you risk burning your hands unless you hold the hanger with something else (e.g. pliers)
