# The voltage between two points

• Eman 5
In summary, the voltage between points a and b in the circuit is equal to the voltage drop across the 2.5 ohm resistor, which is 7.5V. This can also be determined by finding the potential difference in any branch connected to points a and b.
Eman 5

## Homework Statement

I want to know the voltage between a and b in the drawing below.[/B]

V= IR

## The Attempt at a Solution

The resistors 5Ω and 5Ω are in series:
(Req)1= 5+5=10Ω
The resistors (Req)1, 5Ω and 10Ω are in parallel:
1/(Req)2= 1/10+1/5+1/10=2/5
(Req)2=2.5Ω
The resistors (Req)2 and 2.5Ω are in series:
Rt=2.5+2.5=5Ω
I=V/Rt=15/5=3A
The voltage between a and b= IR
I have I but I don't know how to get R between the two points.

#### Attachments

• i1lnD.jpg
27.4 KB · Views: 667
Edited: Start by finding the total current put out by the battery. Then consider the voltage drop across the 2.5 Ω resistor.

@Eman 5
You should know that iR, in this case, is the voltage drop between any branch in the circuit you drew, i.e. you can consider any branch of them to determine the voltage drop (potential difference) between the points a and b, because all branches in this circuit are connected to the points a and b.

For example, consider the above branch which has the battery and the 2.5 ohms resistance. Remember that the current passing through that branch is 3A.

Now determine the potential difference through that branch.

cnh1995 and Eman 5
The voltage across 2.5Ω resistor=IR=3×2.5=7.5V
The voltage drop across the above branch= 15−7.5=7.5V
Is this correct?

Eman 5 said:
The voltage across 2.5Ω resistor=IR=3×2.5=7.5V
The voltage drop across the above branch= 15−7.5=7.5V
Is this correct?
Yes.

## What is the voltage between two points?

The voltage between two points is the difference in electric potential between those two points. It is a measure of the potential energy per unit of charge that is available at those two points.

## How is the voltage between two points measured?

The voltage between two points is measured using a voltmeter, which is a device that measures the potential difference between two points in an electric circuit.

## What factors affect the voltage between two points?

The voltage between two points is affected by the amount of charge present, the distance between the points, and the material properties of the medium between the points.

## What is the unit of measurement for voltage?

The unit of measurement for voltage is volts (V). One volt is equivalent to one joule of energy per coulomb of charge.

## How is the voltage between two points related to electric current?

The voltage between two points is related to electric current through Ohm's law, which states that the current through a conductor is directly proportional to the voltage and inversely proportional to the resistance. In other words, as the voltage increases, the current increases, and as the resistance increases, the current decreases.

• Introductory Physics Homework Help
Replies
3
Views
1K
• Introductory Physics Homework Help
Replies
13
Views
1K
• Introductory Physics Homework Help
Replies
4
Views
2K
• Introductory Physics Homework Help
Replies
3
Views
2K
• Introductory Physics Homework Help
Replies
4
Views
1K
• Introductory Physics Homework Help
Replies
10
Views
2K
• Introductory Physics Homework Help
Replies
3
Views
654
• Introductory Physics Homework Help
Replies
4
Views
1K
• Introductory Physics Homework Help
Replies
3
Views
664
• Introductory Physics Homework Help
Replies
8
Views
17K