Which transducer is used to produce audible signals such as alarms?

• A. Bells & Buzzers
• B. Indicator lamp
• C. Lighting lamp
• D. Motor

Answer: (A)

Audible alarms require a device that converts electrical energy into sound energy. Bells and buzzers do this by using a vibrating element—an electromagnet drives a bell or a buzzer disk, producing audible vibrations that create sound waves. This makes them ideal for alarms you can hear. The other options provide visual signals rather than sound: indicator lamps and lighting lamps emit light, not noise. A motor turns electrical energy into motion and isn’t intended to generate a controlled audible signal for signaling.