## Chapter 29: Magnetic Fields

 What is a magnetic field? What is the nature of the sources of magnetic fields? What is meant by magnetic field lines? What kind of force does a magnetic field exert on a charge? on a current in a wire? on charges in a wire when the wire is moved through the magnetic field? Show how to evaluate the torque exerted by a magnetic field on a current loop. How does a moving charge behave when it enters a uniform magnetic field? How can you calculate the radius of curvature of the path of a charge in a magnetic field? Explain the operating principles of a mass spectrometer? Explain how to use a magnet and an electric field to make a velocity selector for a mass spectrometer so that only particles with a specified velocity enter the instrument. Describe the Hall effect. How is it useful? What is a magnetic dipole? What is the role of the Earth's magnetic field in producing the aurora? Describe the operating principles of a cyclotron. What is a proton synchrotron? *Magnetic field *Magnetic field of a current *Bar magnet *Magnetic field of the Earth *Electromagnet *Magnetic force *Torque on current loop *Magnetic moment *Centripetal acceleration *Charges in magnetic field *Mass spectrometer *Velocity selector *Hall effect *Aurora *Cyclotron
Index
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## Chapter 30: Sources of Magnetic Field

Describe the role of electric current as a source of magnetic field.

How do you calculate the magnetic field produced by current in a wire (Biot-Savart law)?

Describe Ampere's law and the conditions under which it can be used to calculate magnetic fields.

Use Ampere's law to calculate the magnetic field from an infinite straight wire.

How can the Biot-Savart law by used to find the magnetic field from a finite straight wire?

Describe the force on a straight, current-carrying wire.

Describe the force between two straight conductors.

Describe the magnetic field of a current loop.

Show how to calculate the field at the center of a current loop using Biot-Savart law. How do you calculate the field on axis?

What is a solenoid?

Show how Ampere's law can be used to obtain the magnetic field inside a long solenoid.

Show how the Biot-Savart law can be used to evaluate the field in a finite solenoid.

## Optional topics: Magnetic materials

Describe the three main classes of magnetic materials: paramagnetic, diamagnetic, and ferromagnetic.

What is hysteresis?

Describe a magnetic dipole. Are all magnetic sources dipoles?

What is meant by "magnetic moment"? What is the magnetic moment of an electron?

What is origin of the electron's magnetic moment?

Describe Gauss' law for magnetism. What do we learn from it?

*Electric current

*Biot-Savart law

*Ampere's law

*Magnetic field of straight wire

*Magnetic field geometry

*Magnetic field: finite wire

*Magnetic force on conductor

*Force between conductors

*Magnetic field of current loop

*Field at center of loop

*Field on axis of loop

*Solenoid

*Electromagnet

*Ampere's law for solenoid

*Finite solenoid

*Paramagnetism

*Diamagnetism

*Ferromagnetism

*Hysteresis

*Torque on a current loop

*Magnetic moment

*Electron spin

*Spin magnetic moment

*Gauss' law for magnetism

Index
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