Which formulas describe the magnetic field/field lines?

[ahxbshe1]

hello!
im not very familiar with electromagnetic fields and classical physics, so i turn to you for help,
a problem:
assume you have a magnetic dipole in center (0,0) of a xy plane,
i want to plot the vector of the field at an arbitary point on this plane,and to plot the filedlines, how do i do this? which formulas describe the magnetic field/fieldlines?
thankyou verymuch
ahxbshe

 

[berkeman]

hello!
im not very familiar with electromagnetic fields and classical physics, so i turn to you for help,
a problem:
assume you have a magnetic dipole in center (0,0) of a xy plane,
i want to plot the vector of the field at an arbitary point on this plane,and to plot the filedlines, how do i do this? which formulas describe the magnetic field/fieldlines?
thankyou verymuch
ahxbshe

Welcome to the PF. This web page has a reasonable introduction to magnetic field. Does it help?

http://en.wikipedia.org/wiki/Magnetic_field

.

 

[tomcue]

Hello ahxbshe,

To calculate the magnetic field at an arbitrary point on the xy plane, you can use the formula for the magnetic field of a magnetic dipole:

B = (μ0/4π) * (3r̂ * m̂ - m * r̂) / r^3

Where B is the magnetic field, μ0 is the permeability of free space, r̂ is the unit vector pointing from the dipole to the point of interest, m̂ is the unit vector in the direction of the dipole moment, m is the magnitude of the dipole moment, and r is the distance from the dipole to the point of interest.

To plot the field lines, you can use the formula for the magnetic field lines of a magnetic dipole:

r = m * sin(θ) / Bθ

Where r is the distance from the dipole, m is the magnitude of the dipole moment, θ is the angle between the dipole moment and the point of interest, and Bθ is the component of the magnetic field perpendicular to the dipole moment.

I hope this helps! Let me know if you have any further questions or need clarification.