Physics Demonstrations at Cal Poly Pomona
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Title:
Description:
Demonstrates that molten glass is a conductor of electricity.
Equipment:
1. 250W flood lamp & 40W light bulb on a 110V AC series circuit board
2. Hammer
3. Nail
4. Glove
5. Propane torch
6. Large plastic tray
Procedure:
1. Set the circuit on a plastic tray to catch broken glass. Plug the unit in and the incandescent bulb should come on. Place the plastic bottle over the light bulb to act as a shield.
2. Hold the nail on the top of the shield and hit it lightly with the hammer to break the bulb glass. Carefully lift the shield and using the gloves, remove any shards of glass from the base of the bulb.
3. Heat the glass at the stem of the filament until it liquefies. The spotlight begins to glow, showing conductivity.
