# Find the direction and magnitude of the net magnetic field

• cy19861126
In summary, the two wires carrying currents of 5.00 A in opposite directions and separated by 10.0 cm result in a net magnetic field of 0 at a point midway between the wires. At point P1, 10.0 cm to the right of the wire on the right, the net magnetic field is 5*10^-6T out of the page, and at point P2, 20.0 cm to the left of the wire on the left, the net magnetic field is 1.7*10^-6T out of the page. The directions are determined by the cancellation of the magnetic fields from the two wires.

## Homework Statement

The two wires shown below carry currents of 5.00 A in opposite directions and are separated by 10.0 cm. Find the direction and magnitude of the net magnetic field a) at a point midway between the wires b) at point P1, 10.0 cm to the right of the wire on the right, and c) at point P2, 20.0 cm to the left of the wire on the left.

B = uI/2(pi)r

## The Attempt at a Solution

I got an answer for this, but I'm not sure because my instructor has never gone over vector addition in 3D nor in magnetism. Based on what I learned before, this is what I got
a) 0. because both magnetic field are at the same magnitude but opposite direction. Therefore, their magnitudes cancel and the resultant is 0

b) B = 1.26*10^-6*5.00/(2*3.14*0.1) = 1*10^-5T
B = 1.26*10^-6*5.00/(2*3.16*0.2) = 5*10^-6T
Bnet = 1*10^-5T - 5*10^-6T = 5*10^-6T out of the page
c) B = 1.26*10^-6*5.00/(2*3.14*0.2) = 5*10^-6T
B = 1.26*10^-6*5.00/(2*3.14*0.3) = 3.33*10^-6T
Bnet = 5*10^-6 - 3.3*10^-6 = 1.7*10^-6T out of page

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How did you get the direction of the field for part a?

robb_ said:
How did you get the direction of the field for part a?
There's no direction because the two direction from the two wires cancel out. One is going into the page and another one is going out of the page

## 1. What is the difference between direction and magnitude of a magnetic field?

The direction of a magnetic field refers to the path that a compass needle would take when placed in the field. It is represented by arrows pointing towards the south pole of a magnet. Magnitude, on the other hand, refers to the strength of the magnetic field at a specific point and is typically measured in units of tesla (T) or gauss (G).

## 2. How do you determine the direction of the net magnetic field?

The direction of the net magnetic field can be determined by using the right-hand rule. If you point your thumb in the direction of the current, the direction of your fingers will indicate the direction of the magnetic field.

## 3. What factors affect the magnitude of the net magnetic field?

The magnitude of the net magnetic field is affected by the strength of the source magnet, the distance from the source magnet, and the orientation of the magnet in relation to the point where the magnitude is being measured.

## 4. Can the direction and magnitude of the net magnetic field change?

Yes, the direction and magnitude of the net magnetic field can change. This can happen if the source magnet is moved, if the orientation of the magnet changes, or if the strength of the magnet changes.

## 5. How is the net magnetic field calculated?

The net magnetic field is calculated by adding the individual magnetic fields of all sources in the given area. This can be done using vector addition, where the direction and strength of each magnetic field are taken into account.