Thursday, July 2, 2015

fluid dynamics - Why exactly does a boomerang return back to the thrower?


I was always intrigued by the phenomena that govern the returning back of a boomerang to the thrower.


Even if it is dependent on various factors such as velocity, aerodynamics, wind resistance and so on I was wondering, there must be some concise explanation to it?




Answer



Fundamentally, a boomerang has two arms that spin. One arm spins in the same direction of flight and the other spins away from the direction of flight. For this reason, there's a tilt force on the boomerang.


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Now, since the boomerang is spinning it has angular momentum. Therefore the tilt force generates precession which is pretty much what makes the boomerang come back.


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Full explanation here.


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