1.   A light actuated by a motion detector.

2.   A motion detector to thwart burglaries.

3.   A motion detector can sense movement.

4.   Along several border stretches, the authorities also installed steel fences, searchlights, motion detectors and video cameras.

5.   At nearby Mount Rushmore, a man-made national monument, climbing is forbidden and enforced with motion detectors and patrols of the area.

6.   Automatic fans come equipped with motion detectors to turn on when someone enters the bathroom or humidity detectors to turn on when the humidity in the bathroom rises.

7.   Both operate in an obscure business selling motion detectors and other devices built into larger machinery.

8.   After the war, he used that technology to create motion detectors for alarm systems.

9.   Electronic sensors, including a motion detector and temperature gauge, were placed strategically around the infamous bolt.

10.   He uses a number of devices that help him do his job, like a motion detector on his computer that lets him type by raising his eyebrows.