AP Physics Magnetic Fields Vocab

Magnets

Made up of conductors

Magnetic domains

What do the arrows in a magnetic domain represent?

The direction of spin for valence electrons

Ferromagnetic

Conductor that becomes a magnet once inside a magnetic field

Magnetic declination

Difference in angle between geographic and magnetic north/south

Solenoid

A coil or loop of wire (needs a current)

Electromagnet

Magnet when there is a current in a wire

Velocity selector questions

Motion of ion in a straight line (forces must balance)

Mass spectrometer questions

Find the radius of the path for a charge

Faraday’s Law

Any change in flux will induce a current in that conductor

Magnetic flux

The number of magnetic field lines that pass through a conductor

When the wire is parallel to B field there is ____ flux

little to no

When the wire is perpendicular to B field there is ____ flux

max

Lenz’s Law

A current induced in a conductor produces a B field opposite the first

Motional emf

A voltage is created in a conductor because of a change in flux

What are the results of a change in flux?

A voltage is created, there is an induced current and B field opposite the first

Transformers

Change the voltage of an AC supply

For transformers, what relationship is there between the voltage and the number of loops?

Direct

For transformers, what relationship is there between the voltage and current?

Indirect

What does AC create?

A change in flux

Motor

Changes electrical energy into mechanical energy

Generator

Changes mechanical energy into electrical energy

What causes magnetism inside the atom?

The electrons’ movement is able to generate a current and creates magnetism

What is the unit of magnetic declination?

Degrees