Brian F. answered • 08/08/19
Ex-Apple 🍏 Engineer Tutoring Math to the Tik Tok Generation
The scenario that jumps to my mind is the use of wheatstone bridges as sensors.
As you may know, a balanced wheatstone bridge means all 4 legs of resistance have the same value. hence balancing the bridge. Some sensors, such as RTDs (temperature sensors) and strain gages are what you would call quarter-bridge sensors. In a nutshell, they are one leg of a wheatstone bridge. For temperature, the resistance changes as temperature changes, and as the strain gage experiences strain, the resistance changes. Now, as this one leg of the wheatstone bridge changes resistance and the other legs of the bridge remain unchanged, the bridge becomes unbalanced, and a voltage develops. This is your generated voltage. However, in order to have a generated voltage, you need a voltage source to be applied to the wheatstone bridge--this is your excitation voltage.
