Â­TÂ­here are many different ways to create a motion sensor. For example: 1  It is common for stores to have a beam of light crossing the room near the door, and a photosensor on the other side of the Â­room. 2  When a customer breaks the beam, the photosensor detects the change in the amount of light and rings a bell.
Definition of weir. 1  1 : a fence or enclosure set in a waterway for taking fish. 2  2 : a dam in a stream or river to raise the water level or divert its flow.
1. flowing out or forth. n. 2. something that flows out or forth; outflow; effluence. 3. a stream flowing out of a lake, reservoir, etc. 4. sewage or other liquid waste that is discharged, as into a body of water. [1720â30; < Latin effluent-, s. of effluÄns, present participle of effluere to flow out =ef- ef- + fluere to flow]