How does a Wheatstone bridge work in load cell applications?

Load cells use four strain gauges arranged in a Wheatstone bridge configuration. When load is applied, two gauges in tension increase resistance while two in compression decrease resistance, creating bridge imbalance proportional to load. This full-bridge arrangement provides temperature compensation (all gauges affected equally), doubles sensitivity compared to half-bridge, and produces output voltage proportional to applied force. Typical sensitivity is 2-3 mV/V at full scale.