What are the two possible states of a Wheatstone bridge circuit?

In a Wheatstone bridge circuit, the two possible states are indeed balanced and unbalanced. When the bridge is balanced, the ratio of the resistances in one leg of the bridge is equal to the ratio of the resistances in the other leg, which results in no potential difference across the galvanometer (the device that measures the current). Therefore, there is no current flowing through the galvanometer, indicating a state of balance.

On the other hand, when the bridge is unbalanced, the ratio of resistances is not equal, causing a potential difference across the galvanometer. This difference results in a measurable current through it, indicating that the circuit is not in equilibrium. The balanced state is critical for precise measurements in applications such as strain gauges or temperature sensors, while the unbalanced state is typically what is measured to determine the unknown resistance or to identify changes in the parameters being monitored.

Understanding these states is crucial for applications involving sensor technologies and other electronic instrumentation where accurate resistance measurements are required. This knowledge is fundamental for Biomedical Equipment Technicians who work on diagnostic and monitoring equipment utilizing bridge circuits.