1. What is a Wheatstone Bridge?

The Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component.

2. How Does the Calculator Work?

The calculator uses the Wheatstone bridge formula:

Where:

• \( R_x \) — Unknown resistance (Ω)
• \( R_1 \) — Known resistor (Ω)
• \( R_2 \) — Known resistor (Ω)
• \( R_3 \) — Known resistor (Ω)

Explanation: When the bridge is balanced (zero current through the galvanometer), the ratio of resistances in the two branches are equal.

3. Importance of Wheatstone Bridge

Details: The Wheatstone bridge provides extremely accurate measurements of resistance and is widely used in strain gauge and sensor applications.

4. Using the Calculator

Tips: Enter all three known resistances in ohms (Ω). All values must be positive numbers. The calculator will determine the unknown resistance (Rₓ).

5. Frequently Asked Questions (FAQ)

Q1: What is the balance condition in a Wheatstone bridge?
A: The bridge is balanced when the voltage between the two midpoints is zero, meaning no current flows through the galvanometer.

Q2: What are typical applications of Wheatstone bridges?
A: They're used in strain gauges, thermistors, light detectors, and other precision measurement applications.

Q3: How accurate is the Wheatstone bridge method?
A: Very accurate - it can measure resistances with precision up to 0.1% or better when properly calibrated.

Q4: Can I use this for very small resistances?
A: For resistances below 1Ω, a Kelvin bridge (modified Wheatstone bridge) is more appropriate.

Q5: What happens if the bridge isn't balanced?
A: An unbalanced bridge produces a voltage difference that can be measured and used to calculate the unknown resistance.