Effects of homogeneous and inhomogeneous magnetic fields on particles

AI Thread Summary
The discussion explores the effects of homogeneous versus inhomogeneous magnetic fields on various particles, including charged particles, polarized particles, and magnetic dipoles. A stationary charged particle experiences no force in a homogeneous field, while an inhomogeneous field can exert a force. Neutrons, being neutral, are unaffected by uniform fields but respond to field gradients due to their magnetic moment. Moving charged particles experience a Lorentz force in both types of fields, while magnetic dipoles experience forces only in inhomogeneous fields. The torque on polarized particles in a homogeneous field depends on their alignment with the field lines, raising questions about the effects of inhomogeneous fields on them.
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Hi,
To understand the difference between uniform magnetic fields and field gradients would it help to make comparisons between their effects on different particles? The posts on Stern-Gelach shed some light here.
For instance, what effect would a homogeneous and an inhomogeneous magnetic field have on the following three particles in both a stationary and moving (constant speed) state – charged particle, polarized particle and magnetic dipole? Would these three particles work best for the comparison?
Thank you.
 
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Yes, that's a good starting point. As the simplest example, a neutron, having no charge, is unaffected by uniform field. However, having a magnetic moment, it is affected by a magnetic field gradient.
 
So would it be correct to say that for the moving charged particle, both the homogeneous and inhomogeneous fields are going to produce a Lorentz Force = qv X B perpendicular to both the direction and the field. For the stationary charged particle there will be no force in a homogeneous field, but what about an inhomogeneous field?

For a magnetic dipole there will be no force in a homogeneous field, but a force in an inhomogeneous field while moving and stationary according to F = V(m.B), where V is the gradient.

For a polarized particle, the homogeneous field will only produce a torque on the particle if it is not aligned to the field lines. Will the inhomogeneous produce a different force on the polarized particle?
 
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