For Aboriginal people the boomerang is a symbol of cultural endurance and a tangible link to their long presence on this continent. The boomerang features in Aboriginal creation mythology, and for Aboriginal people the boomerang is considered as old as the continent. The Old Men carved their boomerangs in preparation for battle. They were Dreamtime Men and they sat carving boomerangs so that they could go and attack other Old Men. Boomerang with carving of horse and cow, South Australia, about National Museum of Australia.
The Dreaming extends from the past into the present. In the Dreaming many significant features — rivers, rock formations and mountains — were created when Ancestors threw boomerangs and spears into the earth.
For Aboriginal people the boomerang is as old as creation and a symbol of the enduring strength of Aboriginal culture. With more than different language groups it is understandable that boomerang-making varies across the continent.
Larger, heavier boomerangs are used by inland and desert people; lighter boomerangs are thrown by coastal and high-country people. The vast majority of boomerangs are of the non-returning variety. Carving and colouring of boomerangs differs across the continent; the styles of decoration are as varied as the individual makers. Boomerangs have many uses. They are weapons for hunting birds and game, such as emu, kangaroo and other marsupials.
The hunter can throw the boomerang directly at the animal or make it ricochet off the ground. In skilled hands, the boomerang is effective for hunting prey up to metres away. When hunting for birds, either returning or non-returning boomerangs can be used. So back flip catch we don't actually have to do in competition, I just think its fun to do especially in a crowd or for my friends. Competitors need to understand how boomerangs fly to do well in the sport. So there's actually a lot of physical principles that are operating on a boomerang in flight.
So what makes a boomerang come back includes gyroscopic perception, differential lifts, centrifugal force, momentum of inertia, angular momentum, and torque. Okay, so basically the best way to think of it is that each wing is an airplane wing, and this airfoil allows the boomerang to generate lift, but a boomerang is thrown vertically so the direction of lift is to the side unlike an airplane flying horizontal where the directional lift is up in the air.
So you throw it nice and vertical, straight up and down it'll curve around and come back, and whether it's a two wing boomerang, like the traditional ones that we think of, or three wing boomerang, they're both operating off the exact same principles of flight.
So all boomerangs in the world are thrown straight up and down nice and vertical. You always want the top side of the boomerang facing you. That's the side with the airfoil it's also the side that's painted, and if you're a right handed thrower you want the wind hitting your left cheek coming across from left to right. If your a left handed thrower you'll actually be throwing with the wind coming from right to left. Typically I will pinch grip the boomerang, so I'll use my thumb and index finger to hold it this way.
Sometimes you'll wrap the front finger around the boomerang if you need to get a little bit more power or a little more grip, but there's really no wrong way to do it as long as you are throwing it nice and vertical straight out in front of you, you don't have throw it high, you don't have to throw it low, vertical's probably the most important part.
They come from Australia and they were used as weapons, except that's not exactly true. So the returning boomerang was never actually used as a weapon. What was used as a weapon by the Aborigines called a Kylie, it was much larger and heavier than a typical returning boomerang, and it would travel in a straight line, so almost like an aerodynamic baseball bat that was used to bring down game.
There were civilizations all over the world that had throw sticks. King Tut's tomb in Egypt had throw sticks. The Hopi Indians of the southwest had throw sticks. There's all these different examples of throw sticks being used before we invented bows and arrows and other forms of weaponry, but the returning boomerang was never actually used to hit anything.
By: Tom Harris Updated: Feb 19, Boomerangs probably came about through a trial and error process. See how the experts think boomerangs were invented.
When most of us think of boomerangs , we imagine somebody quite possibly a cartoon character throwing a banana-shaped stick that eventually turns around and comes right back to the thrower's hand possibly after hitting another cartoon character in the head. This idea is simply amazing, and as children, our first reaction to such a device was: This stick is obviously possessed with magical powers! Of course, the person or people who discovered the boomerang hadn't actually found a magical stick, but they had come upon an amazing application of some complex laws of physics.
In this article, we'll break down the physical principles that make boomerangs work, see what happens as a boomerang flies through the air and find out the proper way to throw a boomerang so that it comes back to you.
We'll also delve a little into the history of boomerangs to see how they came about in the first place. Boomeranging is an amazing demonstration of scientific principles as well as a terrific sport you can enjoy all by yourself. When we talk about boomerangs, we usually mean the curved devices that return to you when you throw them, but there are actually two different kinds of boomerangs.
The kind we're all familiar with, returning boomerangs , are specially crafted, lightweight pieces of wood, plastic or other material. Traditionally, these are basically two wings connected together in one banana-shaped unit, but you can find a number of different boomerang designs available these days, some with three or more wings. Most returning boomerangs measure 1 to 2 feet 30 to 60 cm across, but there are larger and smaller varieties.
When thrown correctly, a returning boomerang flies through the air in a circular path and arrives back at its starting point. Returning boomerangs are not suited for hunting -- they are very hard to aim, and actually hitting a target would stop them from returning to the thrower, pretty much defeating the purpose of the design.
Returning boomerangs evolved out of non-returning boomerangs. These are also curved pieces of wood, but they are usually heavier and longer, typically 3 feet 1 meter or more across.
Non-returning boomerangs do not have the light weight and special wing design that causes returning boomerangs to travel back to the thrower, but their curved shape does cause them to fly easily through the air. Non-returning boomerangs are effective hunting weapons because they are easy to aim and they travel a good distance at a high rate of speed. There is also such a thing as a battle boomerang , which is basically a non-returning boomerang used in hand-to-hand combat.
If you throw a straight piece of wood that's about the same size as a boomerang, it will simply keep going in one direction, turning end over end, until gravity pulls it to the ground. So the question is, why does changing the shape of that piece of wood make it stay in the air longer and travel back to you? The first thing that makes a boomerang different from a regular piece of wood is that it has at least two component parts, whereas a straight piece of wood is only one unit.
This makes the boomerang spin about a central point , stabilizing its motion as it travels through the air. Non-returning boomerangs are better throwing weapons than straight sticks because of this stabilizing effect: They travel farther and you can aim them with much greater accuracy.
The returning boomerang has specialized components that make it behave a little differently than an ordinary bent stick. A classic banana-shaped boomerang is simply two wings joined together in a single unit. This is the key to its odd flight path. The wings are set at a slight tilt and they have an airfoil design -- they are rounded on one side and flat on the other, just like an airplane wing. If you've read How Airplanes Work , then you know that this design gives a wing lift.
The air particles move more quickly over the top of the wing than they do along the bottom of the wing, which creates a difference in air pressure. The wing has lift when it moves because there is greater pressure below it than above it.
As you can see in the diagram, the two wings are arranged so that the leading edges are facing in the same direction, like the blades of a propeller. At its heart, a boomerang is just a propeller that isn't attached to anything.
Propellers, like the ones on the front of an airplane or the top of a helicopter , create a forward force by spinning the blades, which are just little wings, through the air. This force acts on the axis , the central point, of the propeller. To move a vehicle like a plane or helicopter, you just attach it to this axis. The classic boomerang's propeller axis is only imaginary, so it obviously isn't attached to anything, but the propeller itself is moved by the forward force of the wings' lift.
So the boomerang is continually turning left, with its faster rotating arm staying on the outer side of its circular flight path. To summarise: the boomerang is hurled into the air almost vertically. It flies roughly parallel to the ground as the flight path curves. Soon it lies down before spinning upwards, all the time still turning left.
From its highest rise the boomerang descends in a glide as it gradually loses forward speed and rotation. Observing returning boomerangs in flight is to enjoy a fascinating phenomenon of physics. They often seem to take a long time to complete a full circle although, in fact, a typical flight lasts only about eight seconds.
The Australian Museum respects and acknowledges the Gadigal people as the First Peoples and Traditional Custodians of the land and waterways on which the Museum stands. Image credit: gadigal yilimung shield made by Uncle Charles Chicka Madden. This website uses cookies to ensure you get the best experience on our website.
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