Understanding Magnetic Field Direction from Two Wires at a Distance

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SUMMARY

The discussion clarifies the magnetic field direction created by two parallel wires, one above and one below the x-axis, with the top wire emerging from the page and the bottom wire going into the page. At a point X located far along the positive x-axis, the magnetic field from the top wire points in the positive Y direction, contrary to initial assumptions that it would point along the x-axis. This is due to the diminishing effect of distance, where the wire appears to be directly on the x-axis, causing the tangent to align vertically. The right-hand rule confirms this orientation, emphasizing the importance of distance in determining field direction.

PREREQUISITES
  • Understanding of the right-hand rule for magnetic fields
  • Basic knowledge of electromagnetic theory
  • Familiarity with vector analysis in physics
  • Concept of magnetic field strength and distance effects
NEXT STEPS
  • Study the right-hand rule applications in electromagnetism
  • Explore the principles of magnetic field lines and their behavior at distance
  • Learn about the Biot-Savart Law and its implications for wire configurations
  • Investigate the relationship between electric and magnetic fields in electromagnetic waves
USEFUL FOR

Physics students, electrical engineers, and anyone studying electromagnetism or magnetic field interactions in wire configurations.

Jstuff
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You have two wires an equal distance above and below the x-axis the top wire comes out of the page and the bottom wire goes into the page.
Finally, consider point X (not shown in the diagram) located on the x axis very far away in the positive x direction. Which of the vectors best represents the direction of the magnetic field created at point X by wire 1 alone?
Hey guys I am confused on this problem I know the answer is the field will point in the positive Y direction, but I do not understand why.
I thought it would point in the positive x direction because of the right hand rule.
How does the fact that the particles are at a very far distance effect the direction of the magnetic field since the direction of the field would not change it would just become weaker. Right?
 
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Sketch a set of axes, and mark on it the top wire, and point X far to the right.
 
I've done this. From this and using the right hand rule the magnetic field would point along the x axis. How does the fact that it is very far away on the axis change the direction of the magnetic field?
 
What is the direction of propagation? What direction is the electric field?
The way I understand this, your E field will be oriented with the wire (+Z), and propagation is in the (+X) direction.
 
Well the direction of propagation to my understanding is to the right in the +X direction. However, the answer is that it propagates in the +Y direction from the top wire which I do not understand.
 
This question was posted 6 years ago, but for anyone else confused here's why the the top wire makes a B field that points straight up at a point really far away:

Lets assume you're infinitely far away from the wire. When your that far away, the distance that wire 1 is above the x-axis becomes so small that you can't even see it. Essentially, the wire acts as if its directly on-top of the x-axis. This means that the tangent line on the x-axis infinitely far away is straight up. I hope that makes sense!
 
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