## How do you calculate the value of a Wheatstone bridge?

Wheatstone bridge formula VG = V * [{R1 / (R1 + R2)} + {R3 / (R3 + RX)}] . To measure the unknown resistance RX , we need to vary the resistance R2 until the galvanometer gives zero reading. This means that no current flows through the arm DB, as both the points D and B are at the same potential.

**What is the formula of Metre bridge?**

ρ=Lπr2X ; Where L be the length of the wire and r be its radius.

**Where is R4 in Wheatstone bridge?**

Reference

- If the bridge is balanced, the current will be zero as well. If we know the bridge is balanced, we can discover the value of R4 with the formula. R4 = R3 * R2 / R1.
- Vb = (R4 / (R3 + R4) * Vin) – (R2 / (R1 + R2) * Vin)
- Vb = (R4 / (R3 + R4)) – (R2 / (R1 + R2)) * Vin

### What is the formula to calculate the unknown resistance?

Each time you can calculate the unknown resistance using the formula:unknown resistance(a)=known resistance(b)*L/M. The value is found to be the same for all values of known resistance.

**What is Wheatstone meter bridge?**

Wheatstone bridge, also known as the resistance bridge, calculates the unknown resistance by balancing two legs of the bridge circuit. One leg includes the component of unknown resistance. Samuel Hunter Christie invented the Wheatstone bridge in 1833, which Sir Charles Wheatstone later popularised in 1843.

**What is Wheatstone bridge class 12?**

The Wheatstone bridge principle states that if four resistances P, Q, R, and S are arranged to form a bridge with a cell and key between A and C, and a galvanometer between B and D then the bridge is said to be balanced when the galvanometer shows a zero deflection.

#### How does a Wheatstone bridge measure resistance?

Measure the resistance of No. 1 with this bridge. To obtain a balance, set the sliding key in the center of the bridge wire and adjust the control key, C, until a minimum deflection of the galvanometer or when the voltage reading drops to zero. When the bridge is balanced, measure L1 and L2 using a meter scale.