Describe how a Wheatstone bridge is used to measure small changes in resistance from a strain gauge.

Describe how a Wheatstone bridge is used to measure small changes in resistance from a strain gauge.

• A. A Wheatstone bridge measures strain by converting temperature difference into a voltage.
• B. A Wheatstone bridge balances four resistors; a strain gauge change perturbs one arm, unbalancing the bridge and producing a differential output proportional to the strain, which is then amplified.
• C. A Wheatstone bridge uses a single resistor to measure strain.
• D. A Wheatstone bridge outputs a current proportional to color changes.

Answer: (B)