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Questacon > Kids > Exhibitions & Shows > The Archives > Our Clever Country > Aboriginal Technology Our Clever CountryFood from thoughtIndigenous technologyAboriginal technology takes some effort out of hunting. What’s the problem?Thousands of years before Australian Federation, the indigenous people of this land were collecting food and hunting to survive. Aboriginal Australians have invented a number of labour–saving technologies that make hunting easier. These devices make sure the energy gained from eating food is greater than the energy used in hunting for it. Great solutionsCredited with inventing the boomerang, many Aboriginal groups used this tool mainly for hunting but also in religious ceremonies. The weapon can easily kill a small animal or knock down a larger one. Hunters all over the world have used spears but the ‘woomera’, a type of spear thrower, is a unique Aboriginal invention. How do they work?
A Woomera and two Boomerangs
The woomera (left) is a spear thrower. On the right is a returning boomerang. The other is a non-returning, hunting one. Image by Peter Firus, Flagstaffotos.
A boomerang must be held vertically and thrown with spin. They can travel distances up to 200 m. Boomerangs used for hunting are heavy sticks with a slight curve, which means they can be aimed and thrown in a straight line at high speed. These are termed non-returning boomerangs. The spinning motion of the boomerang gives it stability as it flies. The more familiar returning boomerang is light in weight and has a more curved shape, which causes it to fly back to the thrower. The way that boomerangs work is very complex. Part of the explanation is that boomerangs are flatter on the lower side and more curved on top in a shape called an aerofoil. When a boomerang is in flight, the shape of the boomerang wing and its angle relative to the flightpath (angle of attack) deflects air downward and creates an upward force called lift. Why do bent boomerangs come back? When a curved boomerang spins in flight, the two wings experience different amounts of lift. One wing always enters undisturbed air, while the other wing is faced with air that has been churned up by the first wing, causing less lift. Also, as the boomerang spins, one wing moves in the direction of the boomerang’s flight and has more lift than the other wing which is spinning back. The boomerang tends to flip over but the spinning motion changes this flipping over action into the curved path of the returning boomerang. A woomera is a simple lever that acts to increase the speed at which a spear is thrown, and thus increase the distance it travels. Made of wood, a woomera acts as an extension of the thrower’s arm. Further info, facts and fun
Inventor David Unaipon (1872-1967)
He was the first Aboriginal writer to be published. Image by the Reserve Bank of Australia.
For more info on how boomerangs workhttp://www.howstuffworks.com/boomerang.htm For more info on great Australian Science check out:CSIRO’s Australia Advances http://www.csiro.au/promos/ozadvances |
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Last modified 23 January, 2008
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