Ch. 3 Magnetism and Electromagnetism
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____1.Magnetic field lines around a bar magnet
a. / are only perpendicular to the magnet.b. / spread out from one pole and curve around to the other.
c. / cross back and forth over one another.
d. / are perfectly straight.
____2.Every magnet, regardless of its shape, has two
a. / magnetic poles.b. / magnetic charges.
c. / magnetic fields.
d. / magnetic needles.
____3.Magnetic poles that are unlike
a. / attract each other.b. / repel each other.
c. / do not interact.
d. / point in the same direction.
____4.What is one difference between a galvanometer and an electric motor?
a. / An electric motor causes something to move.b. / A galvanometer uses an electric current.
c. / In an electric motor, the armature spins continuously.
d. / An electric motor uses electrical energy.
____5.To reverse the direction of current in a motor, current is conducted
a. / through the armature.b. / in the direction of rotation.
c. / through the brushes to the commutator.
d. / through the commutator to the armature.
____6.The type of current produced by a battery is
a. / direct current.b. / alternating current.
c. / magnetic current.
d. / induced current.
____7.You can increase the strength of an electromagnet’s field by
a. / decreasing the current in the solenoid.b. / decreasing the number of loops in the solenoid.
c. / using a stronger ferromagnetic material for the core.
d. / winding the coils more loosely.
____8.As Earth’s magnetic poles move, the magnetic declination in a given location will
a. / stay the same.b. / switch to point south.
c. / change.
d. / return to zero.
____9.An electric current produces a(n)
a. / magnetic field.b. / magnet.
c. / solenoid.
d. / insulator.
____10.Electric current from a generating plant is
a. / direct current transmitted at high voltages, but usually used at low voltages.b. / alternating current transmitted at high voltages, but usually used at low voltages.
c. / alternating current transmitted at low voltages, but usually used at high voltages.
d. / direct current transmitted at low voltages, but usually used at high voltages.
____11.Magnetic poles that are alike
a. / attract each other.b. / repel each other.
c. / do not interact.
d. / have the same shape.
____12.The two ends of a solenoid act like
a. / electrons.b. / a compass needle.
c. / a circuit.
d. / poles of a magnet.
____13.A solenoid with a ferromagnetic core is called a(n)
a. / electromagnet.b. / magnetic pole.
c. / lodestone.
d. / temporary magnet.
____14.A device used to measure small currents is a(n)
a. / electric motor.b. / commutator.
c. / armature.
d. / galvanometer.
____15.What device transforms electrical energy into mechanical energy?
a. / an electromagnetb. / an electric motor
c. / a generator
d. / a solenoid
____16.A generator transforms
a. / potential energy into kinetic energy.b. / mechanical energy into electrical energy.
c. / magnetic energy into electrical energy.
d. / friction into electrical energy.
____17.A device that increases or decreases voltage is called a(n)
a. / alternator.b. / transformer.
c. / generator.
d. / turbine.
Completion
Complete each statement.
18.A maglev train floats above its rails due to ______.
19.A galvanometer is a device that measures small ______.
20.When a wire moves up or down repeatedly in a(n) ______, an alternating current is induced in the wire.
21.A step-up transformer is a transformer that increases ______.
22.A(n) ______is a strong magnet that can be turned on and off.
23.A(n) ______is any material that attracts iron and materials that contain iron.
24.When placed near each other, unlike magnetic poles ______each other.
25.A(n) ______is the region of magnetic force around a magnet.
26.A(n) ______is produced around a wire through which a current flows.
27.A solenoid with a(n) ______core is called an electromagnet.
28.The distance that the pointer of a galvanometer moves depends on the amount of ______in the loops of the armature.
29.A current consisting of charges that flow in one direction only is called a(n) ______current.
30.To generate electricity at an electric company, a turbine is attached to the ______of a generator.
Ch. 3 Magnetism and Electromagnetism
Answer Section
MULTIPLE CHOICE
1.ANS:BPTS:1DIF:L2OBJ:Describe a magnetic field.
TOP:n_ch01_006BLM:comprehension
2.ANS:APTS:1DIF:L1
OBJ:Explain how magnetic poles interact.TOP:n_ch01_019
BLM:knowledge
3.ANS:APTS:1DIF:L1
OBJ:Explain how magnetic poles interact.TOP:n_ch01_016
BLM:knowledge
4.ANS:CPTS:1DIF:L2OBJ:Describe how galvanometers work.
TOP:n_ch03_003BLM:application
5.ANS:CPTS:1DIF:L2OBJ:Describe how electric motors work
TOP:n_ch03_004BLM:comprehension
6.ANS:APTS:1DIF:L2
OBJ:Explain how an electric current can be produced in a conductor.
TOP:n_ch03_006BLM:comprehension
7.ANS:CPTS:1DIF:L2
OBJ:Describe the characteristics of solenoids and electromagnets.
TOP:n_ch03_016BLM:comprehension
8.ANS:CPTS:1DIF:L2OBJ:Describe Earth’s magnetic field.
TOP:n_ch01_025BLM:comprehension
9.ANS:APTS:1DIF:L1
OBJ:Explain how electric current is related to magnetism.TOP:n_ch03_020
BLM:knowledge
10.ANS:BPTS:1DIF:L2
OBJ:Describe the function of a transformer.TOP:n_ch03_011
BLM:application
11.ANS:BPTS:1DIF:L1
OBJ:Explain how magnetic poles interact.TOP:n_ch01_002
BLM:knowledge
12.ANS:DPTS:1DIF:L2
OBJ:Identify some characteristics of a magnetic field produced by a current.
TOP:n_ch03_023BLM:comprehension
13.ANS:APTS:1DIF:L1
OBJ:Describe the characteristics of solenoids and electromagnets.
TOP:n_ch03_015BLM:knowledge
14.ANS:DPTS:1DIF:L1OBJ:Describe how galvanometers work.
TOP:n_ch03_012BLM:knowledge
15.ANS:BPTS:1DIF:L1OBJ:Describe how electric motors work
TOP:n_ch03_026BLM:knowledge
16.ANS:BPTS:1DIF:L1OBJ:Describe how a generator works.
TOP:n_ch03_008BLM:knowledge
17.ANS:BPTS:1DIF:L1
OBJ:Describe the function of a transformer.TOP:n_ch03_009
BLM:knowledge
COMPLETION
18.ANS:magnetism
PTS:1DIF:L2OBJ:Identify and describe the properties of magnets.
TOP:n_ch01_042BLM:comprehension
19.ANS:currents
PTS:1DIF:L1OBJ:Describe how galvanometers work.
TOP:n_ch03_042BLM:knowledge
20.ANS:magnetic field
PTS:1DIF:L2
OBJ:Explain how an electric current can be produced in a conductor.
TOP:n_ch03_045BLM:comprehension
21.ANS:voltage
PTS:1DIF:L1OBJ:Describe the function of a transformer.
TOP:n_ch03_050BLM:knowledge
22.ANS:electromagnet
PTS:1DIF:L1
OBJ:Describe the characteristics of solenoids and electromagnets.
TOP:n_ch03_059BLM:knowledge
23.ANS:magnet
PTS:1DIF:L1OBJ:Identify and describe the properties of magnets.
TOP:n_ch01_057BLM:knowledge
24.ANS:attract
PTS:1DIF:L1OBJ:Explain how magnetic poles interact.
TOP:n_ch01_041BLM:knowledge
25.ANS:magnetic field
PTS:1DIF:L1OBJ:Describe a magnetic field.
TOP:n_ch01_046BLM:knowledge
26.ANS:magnetic field
PTS:1DIF:L2OBJ:Explain how electric current is related to magnetism.
TOP:n_ch03_058BLM:comprehension
27.ANS:ferromagnetic
PTS:1DIF:L2
OBJ:Describe the characteristics of solenoids and electromagnets.
TOP:n_ch03_057BLM:comprehension
28.ANS:current
PTS:1DIF:L2OBJ:Describe how galvanometers work.
TOP:n_ch03_043BLM:comprehension
29.ANS:direct
PTS:1DIF:L1
OBJ:Explain how an electric current can be produced in a conductor.
TOP:n_ch03_052BLM:knowledge
30.ANS:armature
PTS:1DIF:L2OBJ:Describe how a generator works.
TOP:n_ch03_049BLM:comprehension