C11 Terms Flashcards
Any object that possesses or can generate a magnetic field
magnet
One of two areas of concentrated magnetic field lines on a magnets surface
magnetic pole
Magnetic dipole
The north and south ends of a magnet
Magnetic field
The force exerted by a magnet
Paramagnetism
Materials that are only slightly attracted to magnets
Domain magnetic
Where most of the magnetic dipoles are pointed in one direction
Permanent magnet
A ferromagnetic material containing enough aligned magnetic domains to make it a permanent magnetic character
The phenomenon observed in materials that are highly permeable to magnetic lines of force because their magnetic domains align with the field reinforcing it. Alighted magnetic domains can produce permanent magnetism
ferrimagnetism
Weaken an external magnetic field by generating an opposite field
diamagnetism
The temperature at which the magnetic field of a substance no longer act
Curie temperature
Where the earths axis is
geographic North Pole
Where the magnetic fields of the earth are pointed strait down
magnetic North Pole
The magnetic field of the earth
geomagnetic field
It is used to determine the direction of a magnetic field
right hand rule of magnetism
A magnet that uses electricity
electromagnet
Magnetism moving electrons
electromagnetic induction
The rotating part of a generator
rotor
The ring of coils surrounding the rotator
stator
The current charges direction
alternating current (AC)
The rate at which AC current changes direction
hertz (Hz)
A machine that converts the energy of a moving fluid into rotational motion
turbine
Assists in transferring electricity from a rotating shaft
commutator
Transfers electricity from a rotating shaft
brush
Converts electrical energy into mechanical energy
motor
What device changes voltage?
transformer
A magnet that has no resistance at low temperatures
superconducting magnet
What feature of ferromagnetic materials makes them different from other materials
They are neutral
What magnetic evidence do we have that the interior of the earth is not just solid rock acting as a bar magnet?
Magnetic north is moving
Why would the lack of a strong geomagnetic field be a problem do the earth?
Solar radiation would kill all life on earth
Does a straight piece of a current carrying wire have magnetic poles?
Yes
Which type of magnetic material is used as the core of an electromagnetic
Iron
What two factors determine the direction of the current induced in the coil of an AC generator
The north and south poles on a magnet
What is the standard AC supply frequency in the US
60Hz
What are two major structural differences between AC and DC generators
DC generators have commutators and brushes, and the magnets are stationary, whereas AC generators gave neither
In which coil of a transformer does the current determine the strength of the magnetic field in the core
The input
When are superconducting electromagnets required?
In particle accelerators
(True or false). The strength of the magnetic field created by an electromagnet depends on the type of material in the core the number of wraps of wire and the amount of current in the wire
True
