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NOVEMBER 2009
Candle in the wind

Blow out a hidden candle


What you’ll need

  • Matches
  • Candle
  • Plate
  • Tall rounded glass

    What you do

    Step 1. Use a lit match to melt a few drops of wax from the base of the candle onto the plate. Using this, stick the candle onto the plate.
    Step 2. Place the saucer on the table and light the candle. Place the glass between you and the candle itself (the glass must be higher than the candle).
    Step 3. Blow hard on the glass from the front and at the level of the candle flame and you will see that the candle goes out immediately as if you had blown through the glass.

    What happened?

    The air current divides on hitting the bottle, clings to the sides and joins up again behind the bottle, forming a strong eddy which hits the flame with almost as much force as blowing directly at the candle. This is known as the Coanda Effect, the tendency of air to follow the curved surface of a wall.
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