Whistle FAQs:


Q: Is whistle that it creates a pure?

A: Yes, or nearly pure, tone.

Q: Is whistle shown in the figure on the right?

A: Yes, and the Galton whistle.

Q: Were whistles used to call for back-up in areas where neighborhood beats overlapped?

A: Yes, and following their success in London, the whistle was adopted by most police in the United Kingdom.

Q: Are whistles unlike the others listed above?

A: Yes, the sound is generated without interaction with a solid; it is truly an aerodynamic whistle.

Q: Was whistle considered the cause for lack of dynamic similarity?

A: Yes, so the swirl was created in a pipe with a contraction having swirl blades followed by an expansion to create the required axial backflow.

Q: Were whistles much quieter?

A: Yes, and were only thought of as musical instruments or toys for children.

Q: Are whistles traditionally used by association football referees and those of other games?

A: Yes.

Q: Is whistle that we tend to think that it is necessary for a forced jet flow to encounter a solid material to create a whistle?

A: Yes.

Q: Are whistles only approximations to this idealized model?

A: Yes.

Q: Is whistle that the internal flow carries both the unstable vortex downstream and the returning feedback signal upstream?

A: Yes.

Q: Is whistle similar in many respects to the hole tone?

A: Yes, and in particular the teapot whistle.

Q: Is whistle essentially the police whistle turned into a torus?

A: Yes, and magnifying its sound making potential.

Q: Are whistles commonly used by referees and umpires in sporting events?

A: Yes.

Q: Is whistle used here since it is in common use?

A: Yes.

Q: Is whistle that the feedback is sufficiently strong that the jet is bodily diverted instead of depending on flow instability vortex development to control it?

A: Yes.

Q: Was whistle being driven by a cavity resonance?

A: Yes.

Q: Is whistle that the tone sounds only with flow through the orifice from outside?

A: Yes, it is an acoustical diode.

Q: Was whistle created by a Helmholtz resonance in the cylinder volume?

A: Yes.

Q: Are whistles sufficient to set the solid material in motion?

A: Yes.

Q: Was whistle created by a rotating asymmetric vortex which created a rotating force vector in the plane of the exit and a rotating dipole sound field?

A: Yes.

Q: Is whistle the Rijke tube?

A: Yes.

Q: Is whistle still used by many forces worldwide?

A: Yes.

Q: Is whistle shown in the figure on the right?

A: Yes.

Q: Is whistle shown in the figure on the right?

A: Yes.

Q: Is whistle constructionally identical to a 'police whistle' but the chamber contains a small ball?

A: Yes, and known as the pea but usually a material such as plastic or hard rubber.

Q: Are whistles not in this category?

A: Yes.

Q: Are whistles in this category?

A: Yes.

Q: Is whistle primarily a byproduct of source motion?

A: Yes.

Q: Are whistles only approximations to this idealized model?

A: Yes.