NCTI INSTALLER TECH QUESTIONS AND ANSWERS
Which orbital shell has a maximum electron capacity of 18 electrons?
The third shell
Why are semiconductor materials not good conductors nor good insulators?
The valence shells are only half-filled
Which of the following best describes a conductor?
Elements that have a small number of electrons in the Valence shell
Which of the following best describes the relationship between an ampere and a
coulomb?
The number of amperes is equivalent to the number of coulombs passing a given point
during one second
How is electric current produced?
From the transfer of energy from valence electron to valence electron because of
applied charges
What prevents the electrons that orbit an atom's nucleus at high speeds from breaking
away from the nucleus due to centrifugal force?
The attraction between the positive and the negative electron
What is 5 kV equivalent to?
5,000 V
Elements without the production or movement of free electrons are considered?
Insulators
What best describes the type of electron flow called random drift?
Free electrons that change orbits in a random manner, resulting in no charge
What is the effective speed of electric current?
186,000 miles per second
,What is another way to create an electromagnet besides stroking a piece of magnetic
metal, such as a piece of iron with another magnet?
Wrap a coil of insulated wire around an iron bar and pass an electric current through the
wire
Which of the following is true about magnetism?
Magnetism was discovered when the Greeks noticed that certain stones attract iron
What happens in a magnetic material where some of the magnetic domains are pointing
in the same direction?
The magnetic field is weaker
What determines the strength of an electromagnetic field?
An electromagnetic field is determined by the magnitude of mmf
Which of the following is true when talking about overall magnetic field?
When created by a straight piece of wire, the overall magnetic field is weaker than that
created by forming loops of wire
Which of the following is one of the five basic rules that flux lines follow?
Flux lines always curve around through the body of the magnet to form complete loops
Magnetic poles that are ___ will ___ each other when those poles are near each other?
Alike, repel
Which of the following is true about a permanent-magnet loudspeaker?
It has a cone that moves back and forth in relation to the varying current of the original
sound
What does the left-hand rule for electromagnetism in a wire state?
If you wrap your fingers of your left hand around the wire with your thumb pointing in the
direction of the current flow, your fingers will be wrapped in the direction of the magnetic
field
Why are some materials magnetic while others are not?
, Because in most materials, half of the electrons in each atom spin in one direction while
the other half of the electrons spin in the opposite direction, canceling each other, which
results in no creation of a magnetic field for the atom
(-25) + (42) + (-62) +(20) = ?
-25
(17) x (-19) = ?
-323
(-17) - (-34) = ?
17
-49/-7 =?
7
(20)/(-4) + (-2) x (-10) - (-2) x (7) = ?
29
3 6/9 + 6 1/3 + 9 5/9 = ?
19 5/9
7 3/ 1/4 = ?
1 1/58
8.13 x 0.123 = ?
0.99999
0..1420 = ?
3.7669014
67.84 + 81.786 + 4281.98 = ?
4,431.606
What are the three basic elements of an electrical circuit?
Which orbital shell has a maximum electron capacity of 18 electrons?
The third shell
Why are semiconductor materials not good conductors nor good insulators?
The valence shells are only half-filled
Which of the following best describes a conductor?
Elements that have a small number of electrons in the Valence shell
Which of the following best describes the relationship between an ampere and a
coulomb?
The number of amperes is equivalent to the number of coulombs passing a given point
during one second
How is electric current produced?
From the transfer of energy from valence electron to valence electron because of
applied charges
What prevents the electrons that orbit an atom's nucleus at high speeds from breaking
away from the nucleus due to centrifugal force?
The attraction between the positive and the negative electron
What is 5 kV equivalent to?
5,000 V
Elements without the production or movement of free electrons are considered?
Insulators
What best describes the type of electron flow called random drift?
Free electrons that change orbits in a random manner, resulting in no charge
What is the effective speed of electric current?
186,000 miles per second
,What is another way to create an electromagnet besides stroking a piece of magnetic
metal, such as a piece of iron with another magnet?
Wrap a coil of insulated wire around an iron bar and pass an electric current through the
wire
Which of the following is true about magnetism?
Magnetism was discovered when the Greeks noticed that certain stones attract iron
What happens in a magnetic material where some of the magnetic domains are pointing
in the same direction?
The magnetic field is weaker
What determines the strength of an electromagnetic field?
An electromagnetic field is determined by the magnitude of mmf
Which of the following is true when talking about overall magnetic field?
When created by a straight piece of wire, the overall magnetic field is weaker than that
created by forming loops of wire
Which of the following is one of the five basic rules that flux lines follow?
Flux lines always curve around through the body of the magnet to form complete loops
Magnetic poles that are ___ will ___ each other when those poles are near each other?
Alike, repel
Which of the following is true about a permanent-magnet loudspeaker?
It has a cone that moves back and forth in relation to the varying current of the original
sound
What does the left-hand rule for electromagnetism in a wire state?
If you wrap your fingers of your left hand around the wire with your thumb pointing in the
direction of the current flow, your fingers will be wrapped in the direction of the magnetic
field
Why are some materials magnetic while others are not?
, Because in most materials, half of the electrons in each atom spin in one direction while
the other half of the electrons spin in the opposite direction, canceling each other, which
results in no creation of a magnetic field for the atom
(-25) + (42) + (-62) +(20) = ?
-25
(17) x (-19) = ?
-323
(-17) - (-34) = ?
17
-49/-7 =?
7
(20)/(-4) + (-2) x (-10) - (-2) x (7) = ?
29
3 6/9 + 6 1/3 + 9 5/9 = ?
19 5/9
7 3/ 1/4 = ?
1 1/58
8.13 x 0.123 = ?
0.99999
0..1420 = ?
3.7669014
67.84 + 81.786 + 4281.98 = ?
4,431.606
What are the three basic elements of an electrical circuit?
