An explanation of how a boomerang returns to its thrower

Image Source

Hello people of steemopolis,
Could you describe your motion if you had a foot (let say the right foot) moving faster than the other foot (the left)? This scenario could be used to explain the mystical flight of a boomerang.
The boomerang is probably the first devices ever built by man that could glide in the air. About 3 to 4 years ago, I came across this this pun it goes thus.
›What do you call a boomerang that doesn’t come back? A stick!

Funny right? I thought so too (if you didn’t find it funny you probably didn’t get the joke, lol).
This joke is quite misleading, it wired me to thinking all boomerangs comes back (or at least are meant to come back) to their throwers. So if it doesn’t cone back, it is not a boomerang! This however isn’t necessarily true. A boomerang that comes back is called a ”returning boomerang”. Oh yes, boomerangs comes in different versions and flavors. I intend explain how a returning boomerang comes back to its thrower. Spoiler alert: It does not make use of GPS technology. 😂

The returning boomerang.

The oldest boomerang discovered is about 20,000 years old and it was found in Poland. The early men used boomerangs to hunt. When a hunting boomerang is thrown, it could cover a distance of 150yards.

How it flies.

People for a long time have been bewildered by the motion of a boomerang. A lot of theories and literature was made trying to explain the flight of this object. A theory had it that a slight twist of a boomerang’s arms was necessary for its performance. At some point this theory was widely accepted as it required less explanation with the “well-understood” propeller at the time then. Sadly, the boomerang, in no way works like a propeller.
Most of the long distance weapons (missiles) that were used by the early men are ballistic in nature (that is: they travel in a vertically curved path and hit the ground afterwards). Examples are stones, spears, arrows and so on. An implication of this is that they (ballistic missiles) must be thrown upwards to keep it in motion for a longer period of time.
A boomerang however, is not a ballistic missile. It can travel parallel to the ground and can resist the earth’s gravitational pull as far as they maintain forward and rotational speed unlike a spear that tends to fall almost as soon as it is thrown (when thrown parallel to the ground).
The boomerang also have other qualities that Improves their motion.
The early men cracked aerodynamics before we did. The way a boomerang was designed explains how it was able to fly the way it did. The qualities of a boomerang was used in the design of airplanes during the 20th century.
One of the properties is the large surface area to body mass ratio. A boomerang was designed in such a way that it’s surface area is larger than its body mass. This is so to increases its gliding time in the air. They are usually have a broad surface (large surface area), thin sides and are light in weight.

The top surface of a boomerang is made to curve outwards a little (convex) while the bottom surface is made nearly flat. When a boomerang is exposed to strong air currents, the air flow make the pressure on the convex surface (the top surface) low and produces packets of high pressure below the wing.
The pressure below and above the wings creates forces that pushes and pulls the wing upwards. Suppose the flow of air is fast enough, there would be an upward lift of the boomerang and it will be held by the air current.

The mystical flight of a boomerang has two components. One is the motion of the boomerang as it glides away from its thrower, usually referred to as the forward motion. The other is rotational motion of its arms. An arm moves forward while another moves
When a boomerang is hurled, tilting the arms slightly upwards will increase its flying ability just as one of the theories made for the explanation of a boomerang’s flight. In contrast to the theory, the twist does not make the boomerang fly, instead, increases its ability to fly.
By convectional wisdom, one would think that a boomerang’s curve was necessary for its performance. You wouldn’t be entirely wrong if you also thought of it; I thought that myself. The curve there is to aid the rotational motion. Supposed a boomerang was made straight, the center of rotation would be stable and it would be changing position and reduce the rotational motion of the arms.
Moreover, a straight object have the tendency to rotate about it’s longest axis, flipping about itself very fast. The presence of a curve in a boomerang prevents the boomerang from rolling, keeps the center of rotation at a point and helps to maintain the speed of the rotation.

How it returns

I explained earlier, a boomerang flight has 2 components in it; a rotational and a forward motion.
Since a boomerang is designed to curve a little, a wing rotates forward while the other rotates backwards.
An arm (the upper) of the boomerang moves with a faster speed with respect to the other arm (the lower). This arm performs both a forward motion and a rotational motion. The lower arm also has a forward motion and a rotational motion but the rotation motion has a relatively slower speed compared to the upper arm.
This brings me back to the question I asked at the beginning of this article.

Could you describe your motion if you had a foot (let say the right foot) moving faster than the other foot (the left)?

The result would be moving in a curved path! So a boomerang will come back to its thrower.
Thanks for reading. I hope you enjoyed this article.

References

1
2
3

---

@geniusvillain