Magnetic Field Strength Vs. Angle of direction

In summary, if you are varying the strength of the magnetic field then the angle of direction around the coil will also vary.
  • #1
carpekd
6
0
I have a simple question... does the magnetic field angle of direction vary when you vary the field strength?

For example, say i have a magnetoresistive sensor, which, to my knowledge only detects the magnetic field angle of direction (unlike a halls, which senses field strength). I place this sensor at a short distance X from a coil. Assuming X is constant, what would the sensor detect if I varied the current in the coil? I'm assuming that the field angle doesn't change with field strength, so the sensor would output a constant reading, but I'm not sure if that is a correct assumption.
 
Engineering news on Phys.org
  • #2
I have a simple question... does the magnetic field angle of direction vary when you vary the field strength?
... the magnetic field is a vector - it assigns to each point in space a magnitude and a direction.
If it is specified that the magnitude is changed then the direction does not change. That what the words mean.

In your example - changing the current in the coil changes the magnitude of the magnetic field everywhere - but the overall shape should not change, so the direction shouldn't. Detectors which register only the direction will not see any change.

It is possible to perform some action that changes both the magnitude and direction of the magnetic field at the same time. i.e. one could expand or contract the coils in the electromagnet.
 
  • #3
carpekd said:
I have a simple question... does the magnetic field angle of direction vary when you vary the field strength?

For example, say i have a magnetoresistive sensor, which, to my knowledge only detects the magnetic field angle of direction (unlike a halls, which senses field strength). I place this sensor at a short distance X from a coil. Assuming X is constant, what would the sensor detect if I varied the current in the coil? I'm assuming that the field angle doesn't change with field strength, so the sensor would output a constant reading, but I'm not sure if that is a correct assumption.

If you are referring to the field around a coil with varying current then the answer is that the field direction at any point will not change This assumes that is a linear system with all parts behaving nicely. However, when there is another field present (e.g. the Earth's field) the field at a point will be the vector sum of both fields. As the field from the coil is reduced progressively, the direction of the resultant will tend to that of the external field. This is just like when you do a mechanics calculation involving strong springs and masses - then you reduce the spring forces until the weight force becomes significant.
 

1. What is the relationship between magnetic field strength and angle of direction?

The strength of a magnetic field is directly proportional to the cosine of the angle between the direction of the field and the direction of the magnetic field lines.

2. How does the angle of direction affect the strength of a magnetic field?

As the angle between the direction of the field and the direction of the magnetic field lines increases, the strength of the magnetic field decreases. This relationship can be represented by the equation B = B0 cosθ, where B is the magnetic field strength, B0 is the maximum field strength, and θ is the angle of direction.

3. Can the angle of direction change the polarity of a magnetic field?

No, the angle of direction does not affect the polarity of a magnetic field. The polarity of a magnetic field is determined by the direction of the magnetic field lines, which are always from the north pole to the south pole.

4. Why does the magnetic field strength decrease as the angle of direction increases?

This is due to the fact that a component of the magnetic field is perpendicular to the direction of the magnetic field lines. As the angle of direction increases, the perpendicular component decreases, resulting in a decrease in the overall field strength.

5. How is the angle of direction measured in relation to the magnetic field?

The angle of direction is measured from the direction of the magnetic field lines to the direction of the field. This angle can be measured using a protractor or a compass. It is important to note that the angle is always measured in the same plane as the magnetic field lines.

Similar threads

  • Electrical Engineering
Replies
14
Views
3K
  • Electrical Engineering
Replies
6
Views
969
  • Electrical Engineering
Replies
2
Views
135
  • Electromagnetism
Replies
2
Views
1K
  • Electrical Engineering
Replies
20
Views
3K
  • Electrical Engineering
Replies
14
Views
2K
Replies
7
Views
3K
Replies
8
Views
1K
  • Electrical Engineering
Replies
7
Views
2K
Replies
41
Views
3K
Back
Top