The correct answer is four. As per the boomerang model (see figure above), there are two sorts of boomerang blades: outspread and circular segment.
Turning around its focal point of mass, a boomerang enacts outspread and latent blades as appeared in pictures beneath.
Spiral blades are dynamic, curve blades are detached
Curve blades are dynamic, spiral blades are detached
The blades in dynamic position communicate with the air to create powers whose rakish force decides two kinds of boomerang gyroscopic precessions.
First kind of boomerang precession
The main kind of boomerang precession is notable to be liable for the boomerang return.
At the point when the boomerang is pushed apparently in a vertical position, it turns with precise speed w and flies with speed v. Spiral blades produce a notable lift power, which influences the turning boomerang when the wind stream gets before them. The lift powers have various qualities for forward and in reverse turning outspread blades as the boomerang is moving ahead. The distinctive lift powers have precise force, applied to the turn hub, which gives the primary kind of gyroscopic precession of the turning boomerang around the Z-hub with rakish speed Omega1. This first sort of gyroscopic precession is answerable for the boomerang’s turning in reverse.
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