Magnetic Fields
Compasses
Magnetism from Electricity
Electricity from Magnetism
Grab Bag
100
What is a magnetic field?
A region where a magnetic force can be deteced.
100
What instrument is used to trace the direction of a magnetic field?
A compass.
100
What is a solenoid?
A coil of wire with an electric current in it.
100
What machine converts mechanical energy into electrical energy?
A generator.
100
The law of conservation of energy says that energy cannot be created or destroyed. Does electromagnetic induction violate this law?
No.
200
Opposite magnetic poles_________.
Attract.
200
What direction would a compass needle point if you were in Australia?
To the geographic north pole.
200
What is an electronmagnet?
A solenoid with a metallic core.
200
A transformer with 500 turns on the primary coil and 200 turns on the secondary coil, is what type of transformer?
Step-down
200
What shape is the magnetic field around a wire?
A circle.
300
Where is the magnetic field of a magnet the strongest?
At the poles.
300
Compasses work, because the magnetic field of the Earth is similiar to that of what?
A bar magnet.
300
What type of device converts electrical energy into mechanical.
An electric motor.
300
Name 2 types of electromagnetic energy.
Radiation, light, heat - infrared, x-rays, gamma rays, UV, radio waves, microwaves, etc...
300
What does Faraday's Law state?
An electric current can be produced in a circuit by a changing magnetic field.
400
If a bar magnet is broken in half, how many north poles and how many south poles will there be?
2 of each
400
If a compass is held directly in front the north pole of a bar magnet, where will the compass point?
Away from the magnet.
400
Will increasing or decreasing the number of coils in a solenoid make it weaker?
Decreasing
400
What is the process of generating an electric current by moving a magnet in and out of a coil of wire?
Electromagnetic Induction
400
The north magnetic pole and geographic north pole are not in the same place. What county is the north magnetic pole in?
Canada
500
Magnetic field lines from a bar magnet leave the ______ pole and enter the ________ pole.
North and south.
500
If the current in a wire is traveling North, what direction will a compass point if it is held directly above the wire?
East.
500
What is the name of the rule for finding the direction of a magnetic field around a current carrying wire?
The right-hand rule.
500
The current induced in the wire is at a maximum when the wire in a circuit moves __________ to a magnetic field.
Perpendicular.
500
Who was the Danish science teacher that first experimented with the effects of an electric current on a compass?
Hans Christian Oersted
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