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Magnetic Moment

  • Thread starter Cball3
  • Start date
1. A spherical shell of radius R has a constant surface charge density, sigma. It rotates about its diameter with angular speed, w. Find the magnitude of the magnetic moment of the rotating spherical shell.

2. Magnetic dipole moment u = NIA(normal vector) ; Torque = u X B; Spherical Volume = 4/3 pi R^3

3. No idea where to start....


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Consider an element of charge dq = σdA on the surface. As it spins around it becomes a current dI. Find the magnetic moment dm generated by this current then add all such magnetic moments over the surface of the sphere.

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