Magnetism I
Areas of concentrated magnetic force
What are magnetic poles?
The first people to use magnetic compasses.
Who are the Chinese?
The prime mover for a hydroelectric power plant.
What is a water turbine?
Most of the electricity that we use in our homes is supplied by this.
What is an AC generator?
The strongest magnets are made out of pure substances
What is false?
The first practical use of natural magnets was _______.
What is navigation?
The SI unit of frequency
What is hertz?
___________ will induce a current in a nearby circuit.
What is a moving electromagnet?
A ferromagnetic material above its Curie temperature will behave like a ______ material when it is placed in a magnetic field.
What is paramagnetic?
A magnet moving back and forth in the center of a coil of wire produces a direct current in the wire.
What is false?
What is a transformer?
An electrical current that regularly changes direction.
What is an alternating current?
Large groups of magnetic dipoles in a material that align to form microscopic magnets.
What are domains?
What are doorbells, relays, remote door locks, tv & computer monitors, sorters at junkyards, etc. ?
Natural magnets, such as lodestones, display ferrimagnetism.
What is true?
Special electrical switches that use electromagnets
What are relays?
Geothermal energy uses a ________turbine.
What is steam?
Current that flows in one direction
What is direct?
The strength and diffraction of magnetic fields are modeled by this.
What are lines of force?
Magnetic fields interact with each other just like electrical fields do.
What is true?
What are two magnetic poles?
Law of magnetism
What is opposite magnetic poles attract and like magnetic poles repel?
A magnet and a _______ will not attract or repel each other.
What is a stationary charge?
The reason power companies use transformers.
Temperature does not have a strong effects a ferromagnetic object.
What false?