Grain Silo explosion: A cloud of power is ignited and blows lid off of can.

• C+70+90

diagram for demo

Lycopodium powder is put on a square of paper which is then placed on top of a funnel connected to a rubber hose. The funnel is inside a coffee can, next to a lit candle. A plastic lid is placed on top of the can. Blowing on the hose tosses the powder into the air. The candle flame ignites the cloud of powder, and the lit pops off the can. This effect can be observed with any fine powder and is the reason why grain silos sometimes explode when fine particles are disturbed and create space at interstitial spaces.

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