PURPOSE: To produce a dust explosion.
DESCRIPTION: A rounded tablespoon of lycopodium powder placed in the funnel is blown upward by blowing into the end of the rubber tube, which can be stretched out. When the cloud of powder reaches a burning candle flame, on the top mount, it ig nites readily to create a dust explosion. This is a very dramatic effect.
SUGGESTIONS: Stand back while blowing. Dress up with a welder's coat, mask, and gloves. Set the device a few feet in front of the first row before igniting the explosion and scare the ghuzzickki out of some students.
REFERENCES: (PIRA 4F10.40) See also Demonstration I1-62: DUST EXPLOSION MODEL, which describes why this effect is so dramatic. The September 1997 issue of HealthSense, the Mid Atlantic Medical Services, Inc. Membership Newsletter, points out that use of powdered sugar on childrens' birthday cakes could lead to this effect when the candles are blown out!!
EQUIPMENT: Lycopodium powder, funnel with rubber hose and candle with matches mounted onto heavy stand as photographed.
SETUP TIME: 5 min.
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