Electronic balances use a device called a "load cell." The full name is "strain gauge load cell."First a little background: a "strain gauge" is a thin device, smaller than a fingernail, which changes electrical resistance when it is stretched or compressed. If you glue a strain gauge onto a metal bar, you can determine how much the bar is bent by measuring changes in electrical resistance of the strain gauge with a meter.Typically, several strain gauges are used in Wheatstone bridge arrangement and they are glued onto the load cell in a protected location.
