Which of the following is a common sensor used in burglar alarm systems?

Motion detectors are widely utilized in burglar alarm systems due to their ability to detect movement within a designated area. These sensors are typically used to sense changes in infrared radiation, which occurs when a person or object moves through their field of view. The primary function of motion detectors is to enhance security by identifying unauthorized movements, which can trigger alerts or alarms.

While fire alarm sensors, carbon monoxide detectors, and smoke detectors play critical roles in overall safety and security systems, their primary focus is not specifically on detecting burglaries. Fire alarm sensors are designed for fire detection, carbon monoxide detectors for gas leaks, and smoke detectors for smoke presence, thus each serving distinct safety functions rather than burglary prevention.

In summary, motion detectors are essential for burglar alarm systems as they provide real-time monitoring and response capabilities to potential intrusions, making them a cornerstone of effective security measures.