Wheatstone Bridge
The Wheatstone bridge is a circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one of which includes the unknown component. It is commonly used in physics experiments and electronic circuits to measure resistances accurately.

Principle
The Wheatstone bridge works on the principle of null deflection, where the voltage difference between two points in the bridge circuit is zero when the bridge is balanced. This condition is achieved by adjusting the known resistances until the bridge is balanced, allowing the calculation of the unknown resistance.

Equation
The balance condition of the Wheatstone bridge is given by the equation:
\(
\frac{R1}{R2} = \frac{R3}{R4}
\)

Applications
- The Wheatstone bridge is used in strain gauge measurements to determine the change in resistance due to strain.
- It is used in temperature sensing circuits to measure temperature-dependent resistances.
- The bridge is also used in impedance measurements in audio circuits.

Problem-solving
When solving problems related to Wheatstone bridges, it is important to understand the balance condition equation and how to manipulate it to find the unknown resistance. By following a systematic approach and applying the principles of the Wheatstone bridge, accurate measurements can be obtained.
In conclusion, the Wheatstone bridge is a versatile circuit that finds applications in various fields of electronics and physics. Understanding its working principle and equation is essential for accurate measurements and problem-solving.