What type of notification device consists of a continuously vibrating membrane or a piezoelectric element?

The correct answer is a horn, which is a notification device that typically uses a continuously vibrating membrane or a piezoelectric element to produce sound. In alarm systems and intrusion detection scenarios, horns are often favored for their ability to emit loud, attention-grabbing alerts.

Horns work by converting electrical energy into mechanical energy, causing a diaphragm to vibrate and generate sound waves. This characteristic allows them to alert individuals effectively over long distances or in noisy environments. The sound produced by horns is usually louder and can carry further than sounds from other devices such as buzzers or speakers, making them suitable for emergency notifications.

While buzzers do produce sound, they usually do so through a simpler mechanism and are not designed for long-range alerting. Speakers are typically used for more nuanced audio output, such as speech or music, rather than for loud emergency notifications. Strobe lights serve a different purpose entirely, providing visual alerts rather than auditory signals.