Magnetic dipole moment

Definition

The magnetic dipole moment is a vector quantity that represents the strength and orientation of a magnetic source, such as a current loop or a magnet. It determines the torque experienced by the object in an external magnetic field.

5 Must Know Facts For Your Next Test

1. The magnitude of the magnetic dipole moment for a current loop is given by $\mu = I \cdot A$, where $I$ is the current and $A$ is the area of the loop.
2. The direction of the magnetic dipole moment is perpendicular to the plane of the current loop, following the right-hand rule.
3. A magnetic dipole in a uniform magnetic field experiences torque but no net force.
4. The potential energy of a magnetic dipole in an external magnetic field is given by $U = -\mu \cdot B$, where $B$ is the magnetic field.
5. Magnetic dipole moments are fundamental in explaining phenomena like nuclear magnetic resonance (NMR) and electron spin resonance (ESR).

Review Questions

• How do you calculate the magnitude of a magnetic dipole moment for a current loop?
• What determines the direction of a magnetic dipole moment?
• What kind of interaction does a magnetic dipole experience in a uniform magnetic field?

Related terms

Torque on a Current Loop: The rotational force experienced by a current-carrying loop when placed in an external magnetic field.

Right-Hand Rule: A mnemonic used to determine the direction of certain vector quantities, such as angular velocity, torque, and magnetic fields.

Magnetic Field: A vector field surrounding magnets and electric currents, representing the force exerted on other magnets and moving charges.