Ngā Whāinga Ako

• To be able to explain the function of a wick

What do you think a wick is for?

Whakakite: Walking Water

Capillary Action

• Liquids can flow into narrow spaces, even against the direction of gravity.
• E.g. paper in water, paint brushes sucking up water, a thin tube in water.
• The surface tension and adhesive forces between the liquid and container propel the water into the narrow space.

• Pātai: Why is capillary action important?
• Whakatika: Because it increases the surface area of the liquid. This allows it to evaporate more easily!
• Fuels need to be gaseous and mixed with oxygen to combust.

Wick Whakamātau

1. Safety
2. Whakamātau read through
3. Check understanding each step
4. Explain must do Qs 1,2,3 during whakamātau
5. Timeframe (20mins)
6. Clean up check

Discussion Points

1. Why didn’t the solid paraffin wax ignite?
2. Did the liquid wax ignite? Why/ why not?
3. How does the wick allow the wax to burn? (think about last lesson’s whakamātau)
4. Why doesn’t the wick burn? (clue: evaporation and sweating)