How Does Temperature Affect a Motion Detector?

Temperature Effects Physical Waves

Invisible waves exist all around us. Certain environmental conditions can change how they behave. Temperature, a unit of measurement in molecules of kinetic energy, is one such factor that can affect a motion detector.

History

Motion detectors generally start working because of change. Set to recognize normal fluctuations in heat or air pressure, for example, these devices can tell when waves are altered in some way. Temperature affects a motion detector by causing motion waves to speed up or slow down. Basic motion detectors often send out false alarm signals when changes occur. Different motion detectors measure various kinds of waves.

Significance

Sensors in a motion detector can detect infrared rays. These are the kind of rays that come from heat or radiation, which exists everywhere already. Objects, such as people or even dogs, all give off a temperature of some kind. Temperature affects a motion detector when heat in a given environment varies from the heat emanating from a person.

Features

Sonic motion detectors use sensors to detect physical waves. Unlike a heat waves, sound waves behave differently, but can be equally affected by temperature. A motion detector can sense when physical waves speed up or slow down. Temperature changes can cause breaks in normal wave patterns.

References

• GlobLab: How Infrared Motion Detectors Components Work
• Batesville High School: Physics Lab - The Motion Detector Demystified

Resources

• MSNucleus: Distinguishing Between Electromagnetic and Physical Waves
• California Institute of Technology (CALTECH): What is Temperature?
• Massachusettes Institute of Technology (MIT): What is Motion?