Quiz 14

Question 1

Benjamin Franklin suggested the convention that opposite charges repel and like charges attract.

True or False?

Answer 1

False

Question 2

The lines of force of a proton flow ? .

a. inward, in all directions
b. inward, in one direction
c. outward, in all directions
d. outward, in one direction

Answer 2

c. outward, in all directions

Question 3

Since the nucleus of an atom has a net positive charge and the electron has a negative charge, the electron is attracted to the nucleus.

True or False?

Answer 3

True

Question 4

Electrons are prevented from being pulled into the nucleus of an atom by ? force.

a. centrifugal
b. centripetal
c. magnetic
d. nuclear

Answer 4

a. centrifugal

Question 5

The Greeks first discovered magnetism over 2,000 years ago when they noticed that a certain type of stone was attracted to ? .

a. amber
b. glass
c. iron
d. light

Answer 5

c. iron

Question 6

Natural magnets were first known by the name ? .

a. cobalt
b. iron
c. magnetite
d. nickel

Answer 6

c. magnetite

Question 7

If a magnet is free to move, the end that is attracted toward the north is called the north pole of the magnet.

True or False?

Answer 7

True

Question 8

A material that retains its magnetic properties is called a permanent magnet, and one that loses this characteristic easily is called a ? magnet.

a. natural
b. saturated
c. temporary
d. weak

Answer 8

c. temporary

DC Theory Textbook, Chap. 8, Pg. 193, “Summary,” Paragraph 2, Sentence 4

Question 9

The cores of temporary magnets are usually made of steel.

True or False?

Answer 9

False

DC Theory Text, Chap. 8, Pg. 193, “Summary,” Paragraph 2, Sentences 4-5

Question 10

In magnetic materials, most or all of the magnetic domains are aligned.

True or False?

Answer 10

True

Question 11

When more magnetic domains of a material line up, the ? of the magnet is increased.

a. permeability
b. polarity
c. reluctance
d. strength

Answer 11

d. strength

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 186, Paragraph 2, Sentence 3

Question 12

The theory of magnetism states that each magnetic ? acts like a small permanent magnet.

a. atom
b. core
c. domain
d. field

Answer 12

c. domain

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 185, Last Paragraph

Question 13

The three basic classifications of magnetic materials are ferromagnetic, paramagnetic, and diamagnetic.

True or False?

Answer 13

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 191, “Types of Magnetic Materials,” Paragraph 1, Sentence 1, and Pg. 193, “Summary,” Last Paragraph, Sentence 1

Question 14

Graphite would fall under the paramagnetic classification of magnetic materials.

True or False?

Answer 14

False

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 191, “Types of Magnetic Materials,” Paragraph 4, Sentence 3

Question 15

Magnetic lines of force are called lines of ? .

a. attraction
b. flux
c. polarity
d. strength

Answer 15

b. flux

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 187, Paragraph 2, and Pg. 194, “Glossary”

Question 16

The flux lines of a magnet leave the north pole and enter the south pole.

True or False?

Answer 16

True

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 186, “Magnetic Reactions,” Paragraph 3, Last Sentence, and Figure 8-5

Question 17

Whenever an electric current flows through a conductor, a magnetic ? is formed around the conductor.

a. circle
b. field
c. force
d. ring

Answer 17

b. field

DC Theory 3rd Ed. Textbook, Chap. 9, Pg. 198, “Magnetic Direction,” Paragraph 1, Sentence 1, and Pg. 206, “Inducing Voltage with Magnetic Fields,” Paragraph 1, Sentence 2, and Pg. 208, “Summary,” Paragraph 1, Sentence 1

Question 18

The direction of current flow through the wire determines the ? of the magnetic field.

a. direction
b. permeability
c. reluctance
d. strength

Answer 18

a. direction

DC Theory 3rd Ed. Textbook, Chap. 9, Pg. 198, Figure 9-1

Question 19

Magnetic lines of flux never cross each other.

True or False?

Answer 19

True

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 190, “Magnetic Flux,” Number 2

Question 20

Some of the flux lines that leave a magnet’s north pole are repelled and do not return to the south pole of the magnet.

True or False?

Answer 20

False

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 190, “Magnetic Flux,” Paragraph 3, Sentence 1

Question 21

The direction of the magnetic field around a current-carrying conductor can be determined by using the right-hand rule for conductors.

True or False?

Answer 21

False

Question 22

The strength of an electromagnet is directly proportional to its ampere-turns.

True or False?

Answer 22

True

DC Theory 3rd Ed. Textbook, Chap. 9, Pg. 200, “Field Strength,” Paragraph 3, Sentence 3

Question 23

Increasing the number of loops will increase the ? of the magnetic field.

a. core
b. permeability
c. size
d. strength

Answer 23

d. strength

DC Theory 3rd Ed. Textbook, Chap. 9, Pg. 200

Question 24

The degree to which a material is able to focus lines of magnetic flux is called ? .

a. flexibility
b. permeability
c. redirection
d. saturation

Answer 24

b. permeability

DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 188, Paragraph 1, Last Sentence, and Pg. 194, “Glossary”

Question 25

The type of core material used in an electromagnet can increase the magnet’s strength. True or False?

Answer 25

True

Question 26

The opposition that materials present to the flow of magnetic lines of flux is called ? . a. impedance b. inductive resistance c. reluctance d. resistance

Answer 26

d. reluctance ## Footnote DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 189, Paragraph 4, and Pg. 194, “Glossary”

Question 27

The point at which the magnetic domains of a material are all lined up is called ? . a. ampacity b. basic impulsive level c. saturation d. transformation

Answer 27

c. saturation ## Footnote DC Theory 3rd Ed. Textbook, Chap. 8, Pg. 186, Paragraph 2, Last Sentence, and Pg. 194, “Glossary”