A hair-raising experiment

There is a toy available called an “Airzooka” which can fire a focused (but harmless) ball of air up to 6 metres (widely available for around £10).

Figure 3a - the Airzooka

This can demonstrate to children that air is an entity. The air leaves the gun and travels in a ball to the target, you can see the localised impact if you fire at a curtain or blind. It is also highly entertaining if the air ball is aimed at the head of a person with long hair as the hair is blown about. If you spray perfume into the gun and then fire it into an assembly of people only the target is aware of the smell initially. This demonstration shows that it is actually the air which was present in the gun that has travelled to the target; it has not merely pushed other air molecules across the room.

Figure 3b - The Airzooka in action
 
(Click on the play icon or you can Download video - right click on link then 'Save target as...')

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