Description
Using a bow and stick, friction is generated to create heat sufficient to ignite tinder and produce fire. The bow, when rapidly moved back and forth, causes the stick to rotate against a wooden base, generating significant heat through friction. This process demonstrates the conversion of mechanical energy into thermal energy, aligning with the principles of the first law of thermodynamics. The demonstration not only showcases an ancient method of fire-starting but also provides a tangible example of how energy transformation can achieve a practical outcome, emphasizing the fundamental concepts of energy conservation and conversion.
PIRA DCS Number
4B60.50
Preparation & Instructions
A notch is cut in a 5/8 to 3/4 inch board. A small hole is cut next to the "V" notch. Wrap the bow drill tightly in the bow. Hold the cedar drill down with a stone that fits in the palm of the hand and has a "dimple" to hold the drill steady. Push down firmly and move the bow back and forth. After about 30 seconds of smoke carefully pull the coal and punk away from the board. Fold over the lint onto the coal and blow gently. Keep smoke near the fume hose. When fire starts drop into a large beaker. After the students have had a good look throw the burning lint into the sink and spray with water.
Safety
There is always the chance of starting a fire or tripping the fire alarm. Use the fume hose to remove smoke. Place fire in sink and turn on faucet.