# Finding the equivalent resistance b/w a and b

• lgmavs41
In summary, the conversation is about a problem that requires finding the equivalent resistance between two points in a circuit. The equations for calculating resistance in series and parallel are mentioned, as well as the use of Kirchhoff's rules. The individual's attempt at solving the problem by redrawing the circuit is described, but they are still confused and seeking suggestions. A helpful link to a tutorial on using Kirchhoff's rules is provided.
lgmavs41

## Homework Statement

The problem is to find the equivalent resistance between a to b.

## Homework Equations

Req in series = R1 + R2 + ... Rn
Req in parallel = inverse of sum of 1/R1 + 1/R2 + ... 1/Rn
Kirchhoff's Rules

## The Attempt at a Solution

Well, I tried redrawing the circuit to figure out which resistors are in parallel and which are in series but it didn't help. The 1 ohm branches off to 9 ohms and 8 ohms; 6 ohms is connected to 8 ohms which forms a series with 3 ohms...(confuses me...). Anyway, I thought I shouldn't be using the Req equations but instead will be using Kirchhoff's rules somehow. I just don't know how to apply it here in this problem. Anyone have any suggestion as to how to start solving it? Thanks in advance

http://img504.imageshack.us/img504/792/lastproblemme5.jpg

#### Attachments

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Thanks for the link. I have some idea now on how to solve it.

## 1. How do I find the equivalent resistance between two points (a and b)?

To find the equivalent resistance between two points (a and b), you can use the Ohm's Law and Kirchhoff's Laws. First, calculate the individual resistances between a and b, then apply Kirchhoff's Laws to find the equivalent resistance.

## 2. What is the importance of finding the equivalent resistance between two points?

Finding the equivalent resistance between two points is important because it helps simplify complex circuits and allows for easier analysis and calculations. It also helps in determining the overall current and voltage in the circuit.

## 3. Can the equivalent resistance between two points be negative?

No, the equivalent resistance between two points cannot be negative. Resistance is a physical quantity and can only have positive values. If the calculated equivalent resistance is negative, it is an indication of an error in the calculations.

## 4. How is the equivalent resistance affected by the arrangement of resistors in a circuit?

The arrangement of resistors in a circuit can affect the value of the equivalent resistance. In series circuits, the equivalent resistance is the sum of individual resistances, while in parallel circuits, it is calculated using the reciprocal of the sum of the reciprocals of individual resistances.

## 5. Is there a shortcut method to find the equivalent resistance between two points?

Yes, there are shortcut methods such as the delta-wye transformation and the Norton and Thevenin equivalent circuits that can be used to find the equivalent resistance between two points. These methods are useful for complex circuits with multiple resistors.

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