Solve Wheatstone Bridge: Homework Statement & Equations

[I'mlost]

Homework Statement

I think I got part A. I'm complete lost with b -d and help would be great

Homework Equations

https://www.physicsforums.com/attachment.php?attachmentid=10986&d=1190644998

The Attempt at a Solution

It think part d is ∆V = [(∆R1 - ∆R2 + ∆R3 –∆R4 ) / 4R ] * Vo But I'm not sure

Homework Equations

The Attempt at a Solution

 

[Astronuc]

See if this explanation helps - http://en.wikipedia.org/wiki/Wheatstone_bridge

In parts b-d, R4 = R + $\Delta R$, and R1 = R2 = R3.

Find an expression for V₀ in terms of R1, R2, R3 and R4, then substitute in the appropriate values.

In part d, one is looking for how much V₀ changes as $\Delta R$ changes.

 

[piercas]

The Wheatstone Bridge is a circuit used to measure unknown resistance values by comparing them to known resistances. It consists of four resistors arranged in a diamond shape, with the unknown resistor (R4) in one arm and the other three resistors (R1, R2, and R3) in the other arms. The circuit is balanced when the ratio of the resistances in one arm is equal to the ratio in the other arm. This allows us to solve for the unknown resistance using the equation:

R4 = (R2/R1) * R3

To solve for the unknown resistance, you can follow these steps:

1. Set up the Wheatstone Bridge circuit with the unknown resistor (R4) in one arm and the other three resistors (R1, R2, and R3) in the other arms.

2. Vary the variable resistor (R2) until the voltmeter reads zero. This indicates that the circuit is balanced.

3. Measure the resistance values of R1, R2, and R3 using a multimeter.

4. Use the equation R4 = (R2/R1) * R3 to solve for the unknown resistance, R4.

For part b, you will need to use the same equation, but this time, you will vary the variable resistor (R1) until the voltmeter reads zero. This will give you the ratio of R2/R1, which you can then use to solve for R4.

For part d, your equation looks correct. To find the change in voltage (∆V), you will need to take the difference between the initial and final values of R1, R2, R3, and R4, and plug them into the equation. This will give you the change in voltage across the bridge, which can then be used to calculate the unknown resistance, R4.