18. Magnetic Dipoles

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Learning Objectives

  • To be able to describe what a magnetic dipole is and to be able to calculate the magnetic dipole moment.
  • To be able to comprehend and explain when a magnetic dipole in an external magnetic field will feel a force and a torque.


Course Notes

Read through the course notes.  The course note files may also contain links to associated animations or interactive simulations. 

The Magnetic Field (PDF)

Learning Activities

Guided Activities

Read through the class slides. They explain all of the concepts from the module.

Slides (PDF)


Do the Concept Questions first to make sure you understand the main concepts from this module. Then, when you are ready, try the Challenge Problems.

Concept Questions

Concept Questions (PDF)

Solutions (PDF)

Challenge Problems

Challenge Problems (PDF)

Solutions (PDF)

Problem Solving Help

Watch the Problem Solving Help video for insights on how to approach and solve problems related to the concepts in this module.

Problem: Torque on a Current Loop

A rectangular loop of current carrying wire is pivoted on one of its sides. That side is horizontal, along the z-direction. The loop sits in a magnetic field in the y-direction, which is vertical. The wire loop is at an angle θ to the vertical because of the torque due to this vertical magnetic field. What is the magnitude of the magnetic field, in terms of the mass of the loop, the current I in the wire, and the angle θ?

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Related Visualizations

The visualizations linked below are related to the concepts covered in this module.


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