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Flashcards in Alternating Current Deck (26)
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1
Q

How does alternating current get its name?

A. Alternating current uses different paths for electron flow
B. Alternating current constantly changes direction in a circuit
C. An alternating current circuit has constant voltage fluctuation
D. An alternating current circuit has a magnetic field when it flows through a circuit

A

B. Alternating current constantly changes direction in a circuit

2
Q

How is alternating current generated?
A. By coiling a wire around an iron core
B. By moving current through a conductor
C. By moving a conductor through a magnetic field
D. By moving a conductor near an iron core

A

C. By moving a conductor through a magnetic field

3
Q

What determines the frequency in an AC circuit?
A. The amount of cycles that occur in a circuit in one second
B. The amount of current that flows from a given source
C. The force of a generator that is being used
D. The speed of a generator divided by four

A

A. The amount of cycles that occur in a circuit in one second

4
Q
Frequency is measured in?
A. Henrys 
B. Reactance
C. Farads
D. Hertz
A

D. Hertz

5
Q
What is the resistance of the passing of magnetic flux lines through a substance called?
A. Inductance
B. Impedance
C. Reluctance
D. Inductive reactance
A

C. Reluctance

6
Q
What is the ability to store electrons in an electrical circuit called?
A. Inductance
B. Capacitance
C. Reluctance 
D. Impedance
A

B. Capacitance

7
Q
What is the resistance in an AC circuit due to the change of current flow called?
A. Reactance 
B. Impedance 
C. Reluctance 
D. Inductance
A

D. Inductance

8
Q
What is the opposition to change in voltage in an AC capacitive circuit called?
A. Capacitive reactance 
B. Capacitance 
C. Impedance 
D. Reactance
A

A. Capacitive reactance

9
Q
What is the generation of a voltage by voltage by the variance of the current flow rate in an AC circuit called?
A. Reactance 
B. Capacitance 
C. Impedance 
D. Inductance
A

D. Inductance

10
Q
What is the opposition to current flow in an AC circuit caused by magnetic lines of flux called?
A. Inductance 
B. Impedance 
C. Inductance reactance 
D. Reactance
A

C. Inductive reactance

11
Q

What is the total resistance of an AC circuit by inductive reactance, resistance, and capacitance reactance called?

A. Inductance
B. Impedance
C. Reactance
D. Reluctance

A

B. Impedance

12
Q

What is the relationship of current and voltage in an inductive circuit?

A. Voltage leads current
B. Current leads voltage
C. Voltage is in phase with current
D. There is no relationship

A

A. Voltage leads current

13
Q

What is the relationship of current and voltage in a capacitive circuit?

A. Voltage leads current
B. Current leads voltage
C. Voltage is in phase with current
D. There is no relationship

A

B. Current leads voltage

14
Q

What is the relationship of current and voltage in a resistive circuit?

A. Voltage leads current
B. Current leads voltage
C. Voltage is in phase with current
D. There is no relationship

A

C. Voltage is in the phase with current

15
Q

One complete sine wave represents?
A. The force of and AC circuit
B. The action of the magnetic flux lines in a AC circuit
C. A complete cycle of a generator
D. The direction of the current through a conductor

A

C. A complete cycle of a generator

16
Q

If the current of a AC circuit changes direction 100 times in one second, the frequency of the power source would be?

A. 100hz
B. 200hz
C. 60hz
D. 50hz

A

D. 50hz

17
Q

On a 120v, 60hz power supply, what leg must be fused?

A. The hot leg
B. The neutral leg
C. The hot and neutral leg
D. A fuse is not needed

A

A. The hot leg

18
Q

On a 240v, 60hz single phase power supply, where is a fuse needed?

A. In one hot leg
B. In both legs
C. In both hot legs and neutral leg
D. In one hot leg and one neutral leg

A

B. In both hot legs

19
Q

When placing a voltmeter across two hot legs of a 240v three phase power supply, what voltage should be present?

A. 120v
B. 480v
C. 240v
D. 277v

A

C. 240v

20
Q

How many degrees are any two legs of a three phase electrical system out of phase with each other?

A. 90 degrees
B. 100 degrees
C. 120 degrees
D. 350 degrees

A

C. 120 degrees

21
Q

On a three phase power supply, what leg must be fused?

A. L1,L2, and neutral
B. L1,L2, and L3
C. L1,L3, and neutral
D. T1,T2, and T3

A

B. L1,L2,and L3

22
Q

The condition indicating the direction of electron flow is known as?

A. Current direction
B. Voltage direction
C. Flux condition
D. Polarity

A

D. Polarity

23
Q

On a 120v power supply, what color of wire is the hot leg?

A. White
B. Black
C. Red
D. Green

A

B. Black

24
Q
On a 120v power supply, what color of wire is he neutral leg?
A. White
B. Black
C. Red
D. Green
A

A. White

25
Q

On a 120v power supply, what color of wire is the grounded leg?

A. White
B. Black
C. Red
D. Green

A

D. Green

26
Q

The purpose of connecting a ground wire to a load is to?

A. Allow a secondary path for electrons during normal conditions
B. Protect the equipment against short circuits
C. Protect the equipment against an electrical short to ground
D. Allow a secondary path for electrons during a grounded condition

A

D. Allow a secondary path for electrons during a grounded condition