A dog whistle (also known as silent whistle or Galton's whistle) is a type of whistle used in the training of dogs and cats. The name dog whistle is often used for both lung-powered whistles as well as electronic devices that emit ultrasonic sound via piezoelectric emitters. The electronic variety are sometimes coupled with bark detection circuits in an effort to curb barking behavior.
These kind of whistles are also used to determine the hearing range of people or for physics demonstrations.
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